United States
Department of
Agriculture
Forest Service
Natural Resources
Conservation
Service
United States
Army Corps
of Engineers
United States
Environmental
Protection Agency
United States
Department of
the Interior
Fish and Wildlife
Service
NA-PR-01-95
FORESTED WETLANDS
Functions, Benefits and the Use of
Best Management Practices
W-'
ijy Wj ,
*4;W'
-------
PR
Regional Center for Environmental Information
US EPA Region III
1650 Arch St.
Philadelphia, PA 19103
Additional copies of this publication can be obtained from
USDA Forest Service, Northeastern Area, 100 Matsonford
Road, 5 Radnor Corp Ctr Ste 200, Radnor, PA 19087-4585.
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Front Cover: Heaths are a common bog vegetation, as
suggested by "Big Heath," the local name
for this black spruce bog in Maine.
Photo: Donald J. Leopold
Back Cover: Labrador Pond, a poor fen in New York
Photos: Donald J Leopold
-------
Forested Wetlands
Functions, Benefits
and the Use of
Best Management Practices
-------
Forested Wetlands
Functions, Benefits, and the Use of
Best Management Practices
AUTHORS
David J. Welsch
Northeastern Area, USDA Forest Service
David L. Smart
USDA Natural Resources Conservation Service
James N. Boyer
Philadelphia District, U.S. Army Corps of Engineers
Paul Minkin
U.S, Environmental Protection Agency, Region III
USDA Natural Resources Conservation Service
Howard C. Smith
Tamara L. McCandless USDI Fish and Wildlife Service
The following people have also contributed significantly to this publication with
source materials, writing, editing, ideas and photography. Their efforts are greatly
appreciated.
Scott Jackson, Dave Kittredge, Sue Campbell, Chris Welch, Alison Whitlock, and
Joseph Larson, Department of Forestry and Wildlife Management, University of
Massachusetts; Mike Phillips, Minnesota Department of Natural Resources;
Larry Klotz and Randy Cassell, Shippensburg University, PA; Joe Emerick,
Cambria County Conservation District, PA; Jim Soper, Carmine Angeloni,
Conrad Ohman, and Jack Jackson, Massachusetts Department of Environmental
Management; Eric Johnson, Northern Logger and Timber Processor Magazine;
Mike Love, Blanchard Machinery Co.; John Conkey Logging Inc.; Barbara Hoffert
Graphic Design; Doug Wechsler, Vireo Project, Academy of Natural Sciences of
Philadelphia; Paul Wiegman, Western Pennsylvania Conservancy; Tony Wilkinson,
Nature Conservancy; Kathy Reagan, Adirondack Conservancy; Robert Gutowski,
and Ann Rhoads, Morris Arboretum, University of Pennsylvania; Donald Leopold,
College of Environmental Science and Forestry, State University of New York;
James Finley, Pennsylvania State University; Steve Koehn, Maryland Department
of Natural Resources; Bob Tjaden, Delaware Department of Agriculture;
David Saviekis, Delaware Division of Water Resources; Barbara D'Angelo, U.S.
Environmental Protection Agency-Region III; Paul Nickerson, and Diane Eckles,
USDI Fish and Wildlife Service; Richard Wyman, E.N. Huyck Biological Research
Station, NY; Tom llvari, Bob Franzen, Carl Langlois, Barry Isaacs, and
Bob Wengrzynek, USDA Natural Resources Conservation Service; Gerald
Tussing, Top of Ohio, Resource Conservation and Development Area; John Lanier,
Vermont Department of Fish and Wildlife; Mary Davis, U.S.A. Corps of Engineers;
Lola Mason, Elon S. Verry, Jim Hornbeck, Ed Corbett, Steve Horsley, Gary Wade,
Bill Healy, Lionel Lemery, Bill Moriarity, Nancy Salminen, Elizabeth Crane, Gordon
Stuart, Mark Cleveland, Jackie Twiss, Jim Lockyer, Roxane Palone, Karen Sykes,
Toni McLellan, Mike Majeski, Rich Wiest, Constance Carpenter, John Currier, and
Gary Peters, USDA Forest Service.
-------
INTRODUCTION
Wetlands are complex and fasci-
nating ecosystems that perform a
variety of functions of vital impor-
tance to the environment and to the
society whose very existence depends
on the quality of the environment.
Wetlands regulate water flow by de-
taining storm flows for short periods
thus reducing flood peaks. Wetlands
~ Atlantic white cedar, Chamaecyparis thyoides, has formed a dense forest in this New
Jersey bog.
protect lake shore and coastal areas by
buffering the erosive action of waves
and other storm effects. Wetlands im-
prove water quality by retaining or
transforming excess nutrients and by
trapping sediment and heavy metals.
Wetlands provide many wildlife habi-
tat components such as breeding
grounds, nesting sites and other criti-
cal habitat for a variety of fish and
wildlife species, as well as the unique
habitat requirements of many threat-
ened and endangered plants and
animals. Wetlands also provide a
bounty of plant and animal products
such as blueberries, cranberries,
timber, fiber, finfish, shellfish, water-
fowl, furbearers and game animals.
Although wetlands are generally
beneficial, they can, at times, ad-
versely affect water quality. Waters
leaving wetlands have shown elevated
coliform counts, reduced oxygen con-
tent and color values that exceed the
standard for drinking water.
While many wetland functions are
unaffected by land management ac-
tivities, some functions can be
compromised or enhanced by land
management activities. Deforestation,
for instance, can reduce or eliminate
the ability of a wetland to reduce
flood peaks. On the other hand, re-
taining forest vegetation on a wetland
can help retain the ability of the soil
to absorb runoff water thus reducing
peak flood flows. In addition, man-
agement of the forest can actually
improve wildlife habitat and produce
revenue to offset the cost of retaining
the wetland for flood control. The
key is to recognize environmental
values and incorporate them into
management decisions.
The purpose of this publication is
to provide an understanding of some
of the environmental functions and
societal values of forested wetlands
and to present an array of Best
Management Practices, or BMP's.
Best management practices are
devices and procedures to be consid-
ered and used as necessary to protect
the environmental functions and
societal values of wetlands during
harvesting and other forest manage-
ment operations.
1
-------
One of the earliest of the currently important definitions,
often referred to as the Circular 39 definition, was developed by
the USDI Fish and Wildlife Service as part of a wetland classifi-
cation system for categorizing waterfowl habitat. This
classification is still used to differentiate between various
wetland types for wildlife habitat purposes.
DEFINITION
The term "wetlands" includes a
variety of transitional areas where
land based and water based ecosys-
tems overlap. They have long been
known to us by more traditional
terms such as bog, marsh, fen and
swamp. And while most people use
these terms interchangeably, to many
who study wetlands these terms have
specific meanings which richly de-
scribe the various wetland
environments they represent. How-
ever, before discussing the meaning
of these traditional terms, we should
look first at some general definitions
of wetlands.
The term "wetlands"...refers to lowlands covered with
shallow and sometimes temporary or intermittent waters.
They are referred to by such names as marshes, swamps,
bogs, wet meadows, potholes, sloughs, fens and river over-
flow lands. Shallow lakes and ponds, usually with emergent
vegetation as a conspicuous feature, are included in the
definition, but the permanent waters of streams, reservoirs,
and portions of lakes too deep for emergent vegetation are
not included. Neither are water areas that are so temporary
as to have little or no effect on the development of moist-soil
vegetation.
Wetlands of the United States, Their Extent and Their Value for
Waterfowl and Other Wildlife (Shaw and Fredine 1956)
The Environmental Protection Agency (Federal Register
1980) and the Corps of Engineers (Federal Register 1982) agree
on the following definition of wetlands, which is used to legally
define wetlands for the purposes of the Clean Water Act.
The term "wetlands" means those areas that are inun-
dated or saturated by surface or ground water at a fre-
quency and duration sufficient to support, and that under
normal circumstances do support, a prevalence of vegeta-
tion typically adapted for life in saturated soil conditions.
Wetlands generally include swamps, marshes, bogs, and
similar areas.
Corps of Engineers Wetlands Delineation Manual (U.S. Army Corps
of Engineers 1987)
2
-------
The Cowardin definition is one of the most comprehensive
and ecologically oriented definitions of wetlands and was devel-
oped by the U. S. Fish and Wildlife Service as part of a wetlands
inventory and classification effort.
Wetlands are kinds transitional between terrestrial and
aquatic systems where the water table is usually at or near the
surface or the land is covered by shallow water...wetlands
must have one or more of the following three attributes:
(1) at least periodically, the land supports predominantly
hydrophytes; (2) the substrate is predominantly undrained
hydric soil; and (3) the substrate is nonsoil and is saturated
with water or covered by shallow water at some time during
the growing season of each year."
Classification of Wetlands and Deepwater Habitats of the United States
(Cowardin et al. 1979).
These definitions are descriptions of the physical attributes of
wetlands and are used chiefly to identify wetlands for regulatory
purposes, but wetlands are more than physical places where
water is present and certain plants grow. Wetlands perform a
variety of unique physical, chemical and biological functions
which are essential to the health of the environment and valuable
to society, but which are also difficult to define or identify for
regulatory purposes.
Wetlands exist between aquatic
and terrestrial ecosystems and are,
therefore, influenced by both. Wet-
lands are lands where water is present
on the soil surface or within the root
zone of plants, usually within about
18 inches of the soil surface. Because
of the presence of water, wetlands
have soil properties which differ from
upland areas. Only hydrophytes,
plants that are adapted to an environ-
ment where water is present in the
root zone either permanently or for
extended periods of time, can survive
in such soils. The type of soil, the
amount of organic matter, the depth
to which the water table will rise, the
climate, and the season and duration
of high water will determine the kinds
of plants that will grow in a wetland.
Therefore, wetland types are identi-
fied, in part, by the kinds of plants
that grow in them and the degree of
surface flooding or the degree of soil
saturation due to a high water table.
Any of these definitions may
suffice for the purposes of protection
and enhancement of wetland func-
tions. However, for regulatory
purposes, it is important to know
that there are several similar defini-
tions in common use, but the one that
currently applies for the regulatory
purposes of the Clean Water Act is the
1987 Corps of Engineers definition.
3
-------
It is easier to avoid negative impacts
on wetlands if the land in question is rec-
ognized as wetland at the beginning of
the planning process. Identifying wetlands
when the land is inundated or flooded
with water is not difficult, but wetlands are
not always inundated and many wetlands
are never inundated.
I
A Buttswell and knees of baldcypress, Taxodium distichum, are indicators
of seasonal high water levels.
Therefore, it is necessary to be able to identify wetlands
by other means. While identification and delineation of wet-
lands under the Clean Water Act is a complex process
involving soils, plant communities and hydrology, there are a
number of easily recognized signs that can be used as indi-
cators that the area may be a wetland and that it thus
deserves further investigation.
~ Sediment deposits on leaves suggest a
period of flooding.
It
Buttressed roots and sediment stained A Watermarks on trunks of these water
trunks indicate seasonal flooding. tupelo, Nyssa aquatica. record past
flood levels in an Illinois swamp
-------
Drift lines, the linear deposits of debris at the base of these silver maple trees, Acer saccharinum,
in this New York wetland record past flood events.
Wetland
Characteristics
~
Water
presence of water at or
near the ground surface
for a part of the year
~
Hydrophytic Plants
a preponderance of plants
adapted to wet conditions
~
Hydric Soils
soil developed under wet
conditions
~ Water stained boulders mark past flood levels.
~ Surficial root systems indicate saturated soils.
5
-------
TRENDS
Unfortunately, the benefits
wetlands provide to society and to in-
dividual landowners are neither
widely understood nor appreciated.
From the 1780's to the 1980's it is es-
timated that the 20 state Northeastern
Area, an administrative unit of the
USDA Forest Service, lost 59 percent
of its wetlands (Dahl 1990). To un-
derstand the forces of change,
consider the Chesapeake Bay water-
shed, which comprises portions of the
states of Delaware, Maryland, New
York, Pennsylvania, Virginia and
West Virginia. The Chesapeake Bay
watershed has lost 9 percent of its
noncoastal marshes and 6 percent of
its inland vegetated wetlands between
the mid-1950's and the late 1970's
(Tiner 1987). Forested wetland losses
during this period were greatest for
the state of Virginia which lost 9 per-
cent of its forested wetlands during a
21 year period (Tiner 1987).It should
be noted for the purposes of data
interpretation that Virginia is inclu-
ded in the Chesapeake Bay data, but
is not included in the data for the
Northeastern Area.
Distribution of Wetland Types in
the Chesapeake Bay Watershed
7% 12%
^ Coastal Wetlands
| Inland Emergent Wetlands
| Inland Forested Wetlands
~ Inland Shrub-scrub Wetlands
| Other Inland Wetlands
After Tiner 1994
U.S.D.A. Forest Service Northeastern Area
Wetland Losses in the Northeastern Area
thousands of acres
State
Estimated Wetlands
National Wetlands
Percent
Circa 1780
Inventory 1980
Change
Connecticut
670
173
-74
Delaware
480
223
-54
Illinois
8,212
1,255
-85
Indiana
5,600
751
-87
Iowa
4,000
422
-89
Maine
6,460
5,199
-19
Maryland
1,650
440
-73
Massachusetts
818
588
28
Michigan
11,200
5,583
-50
Minnesota
15,070
8,700
42
Missouri
4,844
643
-87
New Hampshire
220
200
-9
New Jersey
1,500
916
-39
New York
2,562
1,025
-60
Ohio
5,000
483
-90
Pennsylvania
1,127
499
-56
Rhode Island
103
65
-37
Vermont
341
220
-35
West Virginia
134
102
24
Wisconsin
9,800
5,331
-46
TOTAL
79,791
32,818
-59
Currently, about 12 percent of the wetlands in the
Chesapeake Bay watershed are classified as estuarine or
coastal wetlands (Tiner et al. 1994). Coastal wetland losses
continue to result from conversion to estuarine waters by
rising sea levels, coastal erosion and dredging. Losses
of coastal wetlands to agriculture have increased signifi-
cantly since 1982.
6
-------
Changes in Causes of Estuarine Emergent Wetland
Destruction in the Chesapeake Bay Watershed
Changes in Causes of Estuarine Emergent Wetland
Destruction in the Chesapeake Bay Watershed
12%
11%
4%
61%
44%
38%
1955-79
II Agriculture
~ Urban/Rural Development
~
~
1982-89
Other Development
Estuarine Water
After Tiner 1994
350
300
250
200
150
100
50
322
Urban/Rural
Development
Agriculture
After Tiner 1994
1956-79
Estuarine
Development Water
~ 1982-89
The remaining 88 percent of wetlands in the
Chesapeake Bay watershed are various types of
inland wetlands. Sixty percent of the total wetlands
in the Chesapeake Bay watershed are inland wet-
lands classified as palustrine forested wetlands.
Actually, forested wetlands progress from forested
wetlands to emergent wetlands to scrub-shrub wet-
lands and back to forested wetlands creating a sort
of dynamic equilibrium as individual forests
progress through the various plant successional
stages in response to management activities or
natural phenomena. Palustrine scrub-shrub
wetlands and palustrine emergent wetlands make
up 10 and 11 percent of the total wetlands
respectively. Consequently, appropriate forest
management activities have the potential to
favorably effect more than 60 percent of the
total wetlands in the Chesapeake Bay watershed.
Chesapeake Bay Watershed
NEW YORK
PENNSYLVANI
WEST
Changes in Causes of Palustrine Forested Wetland
Destruction in the Chesapeake Bay Watershed
47%
61%
1956-79
1982-89
Agriculture ~ Ponds
Urban/Rural Development ~ Reservoirs/Lakes
] Other Development
Changes in Causes of Palustrine Forested Wetland
Destruction in the Chesapeake Bay Watershed
o
to
1000
800
600
400
200
954
fond:;
Reservoirs/
Lakes
Agriculture Urban/Rural
Development Development
1956-79 ~ 1982-89
After Tiner 1994
After Tiner 1994
-------
Changes in Causes of Palustrine Shrub-Scrub Wetland
Destruction in the Chesapeake Bay Watershed
16%
13%
17%
1956-79
20%
16%
66%
16%
1982-89
~ Agriculture
~ Urban/Rural Development
~ Other Development
| Ponds
~ Reservoirs/Lakes
Changes in Causes of Palustrine Shrub-Scrub Wetland
Destruction in the Chesapeake Bay Watershed
1000
o
CO
c
<
a>
en
ro
0)
>
<
600
986
244
119
80 |
210,
237
105
27
Agriculture Urban/Rural Other
Development Development
95
Ponds
After Tiner 1994
|~| 1982-89
Reservoirs/
Lakes
After Tiner 1994
Current data indicates the pri-
mary threat to forested wetlands is
conversion to ponds and reservoirs;
a secondary threat is conversion to
agriculture. The threat of conver-
sion, both to agriculture and to
lakes and ponds, has increased sig-
nificantly for palustrine scrub-shrub
and palustrine emergent wetlands.
While figures impart a sense of
the magnitude of what we have lost,
they do not tell the entire story. Pol-
lution, changes in the amount of
water entering a wetland, drainage,
urban development and other activi-
ties which may not necessarily
occur in wetlands, often cause im-
pacts to wetlands and result in
severe degradation and impairment
of function. Many of these impacts
cause changes that are difficult to
detect until related effects become
apparent. At that point, only signifi-
cant contributions of time and
resources can repair the damage.
Wetlands are extremely fragile and,
in many cases, the damage may be
irreversible.
Inland forested wetlands comprise
the largest segment, almost 50 per-
cent, of the remaining wetlands in the
lower 48 states (Tiner 1987). Man-
agement strategies adopted for these
wetlands could have a significant im-
pact on the benefits these wetlands
provide to society in the future.
Changes in Causes of Palustrine Emergent Wetland
Destructionin the Chesapeake Bay Watershed
15%
14%
42%
27%
28%
53%
1956-79
1982-89
| Agriculture | Ponds
I Urban/Rural Development ~ Reservoirs/Lakes
~ Other Development
Changes in Causes of Palustrine Emergent Wetland
Destruction in the Chesapeake Bay Watershed
1000
c
c
<
<
800
600
400 -
200 -
Agriculture Urban/Rural Other
Development Development
1956-79
After Tiner 1994
] 1982-89
After Tiner 1994
8
-------
Classification of Wetlands and Deepwater Habitats
of the United States
WETLAND
CLASSIFICATION
Wetlands are classified by the
USDI Fish and Wildlife Service in a
comprehensive hierarchical method
that includes five systems and many
subsystems and classes. The method
is explained in the Classification of
Wetlands and Deepwater Habitats of
the United States (Cowardin et al.
1979). This classification method
includes the marine system and the
estuarine system which are ocean
based systems and beyond the scope
of this document. The other systems
are the riverine, lacustrine and
palustrine systems. The riverine
system includes freshwater wetlands
associated with stream channels,
while the lacustrine system includes
wetlands associated with lakes larger
than 20 acres. The palustrine system
includes freshwater wetlands not
associated with stream channels,
wetlands associated with lakes of less
than 20 acres and other wetlands
bounded by uplands. Most forested
wetlands are in the palustrine system.
System
Subsystem Class
i Marine -
- Subtidal-
Intertidal-
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Reef
-Aquatic Bed
-Reef
-Rocky Shore
Unconsolidated Shore
Estuarine -
Subtidal-
¦ Intertidal-
C/3
I-
<
H
m
<
x
oc
111
t-
<
5
CL
1X1
UJ
a
w
a
Riverine
Tidal
Lower Perennial-
Upper Perennial-
Intermittent-
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Reef
-Aquatic Bed
-Reef
-Stream bed
-Rocky Shore
-Unconsolidated Shore
-Emergent Wetland
-Scrub - Shrub Wetland
-Forested Wetland
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Rocky Shore
-Unconsolidated Shore
-Emergent Wetland
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Rocky Shore
-Unconsolidated Shore
-Emergent Wetland
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Rocky Shore
-Unconsolidated Shore
-Stream bed
Lacuatrine-
Limnetic-
Littoral-
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Rock Bottom
-Unconsolidated Bottom
-Aquatic Bed
-Rocky Shore
-Unconsolidated Shore
-Emergent Wetland
Palustrine -
-Rock Bottom
Unconsolidated Bottom
-Aquatic Bed
-Unconsolidated Shore
Moss - Lichen Wetland
-Emergent Wetland
-Scrub - Shrub Wetland
Forested Wetland
Cowardin et al. 1979
-------
Wetlands can be more simply
classified into three broad categories
of wetland types, based on the
growth form of plants: (1) marshes,
where mostly nonwoody plants such
as grasses, sedges, rushes, and
bullrushes grow; (2) shrub wetlands,
where low-growing, multi-stemmed
woody plants such as swamp azalea,
highbush blueberry and sweet
pepperbush occur; and (3) forested
wetlands, often called swamps or
wooded wetlands, where trees are
the dominant plants.
However, these classification
systems may be less than ideal for the
purposes of this publication. Informa-
tion more useful for protecting and
enhancing the values of forested wet-
lands may be based on a knowledge
of soils, hydrology and plant and
animal communities present. General
information of this type will be pre-
sented on the following pages for
forested wetlands and other types of
wetlands most often encountered in
association with forest management
operations in the Northeastern Area.
~ Marshes often form along the shallow edges of lakes and streams and are characterized by grasses,
sedges, rushes and other herbs, such as cattail, growing with their lower stems in the water.
10
-------
0)
o
A Scrub-shrub wetlands are characterized by low woody vegetation and may include forested
wetlands that have been harvested and are in the process of regeneration to forest.
~ Forested wetlands often resemble neighboring upland forest with their wetland status evident
only from understory wetland plants such as skunk cabbage.
11
-------
~ Lost Pond, in the Adirondacks of New York, is only a small part ol this bog
which includes the black spruce, Picea mariana, and tamarack, Larix laricina.
forest in the background.
Organic Soil
Wetlands
Bogs
The word bog often evokes a
picture of a pond with a ring of
sphagnum moss, but the term bog
actually describes the larger area of
wet organic soil in which these ponds
occur. Bogs are generally formed in
depressions where the combination of
cool climate and abundant moisture
retard the rate of decomposition re-
sulting in an accumulation of organic
matter. They are hydrologically open
systems, but receive little or no dis-
charge of water from groundwater
aquifers and are, therefore, dependent
on precipitation for moisture. Bogs
produce near normal amounts of sur-
face runoff and may recharge small
HYDROLOGY
Hydrology, the way in which a wetland
is supplied with water, is one of the most
important factors in determining the way
in which a wetland will function, what
plants and animals will occur within it, and
how the wetland should be managed.
Since wetlands occur in a transition zone
where water based ecosystems gradually
change to land based ecosystems, a
small difference in the amount, timing or
duration of the water supply can result in a
profound change in the nature of the wet-
land and its unique plants, animals and
processes.
Hydroperiod is the seasonal pattern of
the water level that results from the combi-
nation of the water budget and the storage
capacity of the wetland. The water budget
is a term applied to the net of the inflows,
all the water flowing into, and outflows, all
the water flowing out of, a wetland. The
storage capacity of the wetland is deter-
mined by the geology, the subsurface soil,
the groundwater levels, the surface con-
tours and the vegetation. The hydroperiod
of coastal wetlands exhibits the daily and
monthly fluctuations associated with tides,
WETLAND WATER BUDGET
Precipitation Evapotranspiration
~ Water budget is the term applied to the net result of all water entering
and leaving the wetland.
whereas inland wetlands tend to show, to
a greater degree, the effects of storm and
seasonal events such as spring thaw, fall
rains and intermittent storm events.
In headwater areas where streams
originate, watersheds tend to be small
and have shallow soils with low water stor-
age capacity. Hydroperiods of wetlands in
headwater areas often show water levels
that rise and fall rapidly in response to lo-
calized storm events which supply the
streams and wetlands with runoff. An ex-
ception is areas where soils are dominated
by sandy glacial deposits. These areas
12
-------
~ Alternating patterns of boreal forest, low vegetation and open water often indicate areas that are bogs
interspersed with areas that are fens.
amounts of water to regional ground-
water systems. The resulting
chemistry produces nutrient poor acid
conditions and less than average pro-
ductivity. However, low tree
productivity is largely offset by high
moss productivity. This causes the
accumulation of peat further restrict-
ing water movement and raising the
HYDROPERIODS
~~ Large Riparian Wetland
— Headwater Wetland
~ Wooded Swamp
JFMAMJJASOND
MONTH
~ Hydroperiod is the seasonal pattern of the water level that results from the combination
of the water budget and the storage capacity for a specific wetland. It provides
a clue as to logical operating season.
tend to have deeper soils, gentler slopes
and more predictable hydroperiods.
Sandy glacial deposits also tend to occur
in colder climates and to be frozen for a
period of the year often providing the op-
portunity to conduct management opera-
tions under frozen conditions.
Larger streams, which receive much of
their water from the combined flows of
many smaller streams, tend to respond
more slowly to precipitation and exhibit
the results of the average conditions over
the larger combined watershed as op-
posed to local storm events.
Hydroperiods of wooded swamps as-
sociated with larger river systems tend to
show water levels that reflect events gen-
eral to the larger area such as fall rains
and spring thaw and are, therefore, more
predictable.
The number of times that a wetland is
flooded within a specific time period, such
as yearly, is known as the flood frequency.
Flood duration is the amount of time that
the wetland is actually covered with water.
It should also be noted that many wet-
lands are never flooded, but the wetland
definition does require the soil to be satu-
rated for at least a part of the growing
season. Only hydrophytes, a relatively
13
-------
BOGS/BLANKET BOGS
m
~ Bogs are formed where climate and ample moisture retard decomposition causing organic matter to accumulate. The spongelike
organic matter holds water intensifying the process and can expand to overlay adjacent areas forming blanket bogs.
water table. This accumulation of wa-
ter and peat is self intensifying and
can eventually result in expansion and
overlaying of adjacent areas with peat
to create blanket bogs.
The dominant vegetation is
adapted to the cold, wet, nutrient
poor, acidic environment and includes
black spruce, tamarack, Atlantic white
cedar, Northern white cedar, alder,
sphagnum moss, sedges and heaths
ubiquitous to bogs such as highbush
blueberry, cranberry and leatherleaf.
¦'Mmk
. ."% V::
*Lv/ I'A.U-¦ i •
•' gi' ' •
' ¦ ¦ ¦}(/. H--I / /
\ A W / / / ' . JT'
1 ; • v.v ^ '¦/,
Northern pitcher plant, Sarracenia purpurea, and round leaved sundew, Drosera
rotundifolia, survive in nutrient poor bogs by trapping and digesting insects
small group of vascular plants with special
adaptations which includes many endan-
gered species, are able to survive in soils
that are saturated for more than a short
period during the growing season. There-
fore, the duration and timing of flooding
and or saturation will limit the number of
species that can survive in the wetland.
Residence time is a measure of the time
it takes a given amount of water to move
Deeply rutted skid trails in wetlands can lower water tables and circumvent
chemical processes by shortening the residence time of water.
into, through and out of the wetland. Since
chemical processes take time and follow
one another sequentially, the degree to
which wetlands can change water chemis-
try is determined to an extent by residence
time. This is one reason why it is important
not to create a channel across a wetland
in the direction of flow, increasing outflow
rate and decreasing residence time.
Wetlands receiving inflow from ground-
water are known as discharging wetlands
because water flows or discharges from the
groundwater to the wetland. A recharging
wetland refers to the reverse case where
water flows from the wetland to the ground-
water. Recharge and discharge are deter-
mined by the elevation of the water level in
the wetland with respect to the water table
in the surrounding area. Riparian wetlands
often have both functions, they are dis-
charging wetlands, receiving groundwater
inflow from upslope areas and they are re-
charging wetlands in that they feed lower
elevation groundwater through groundwater
outflow. The same wetland may be a dis-
charging wetland in a season of high flow
and a recharging wetland in a dry season.
Seeps at the base of mountains are often
discharging wetlands formed by groundwa-
ter breaking through to the surface of the
14
-------
Other plants adapted to this environ-
ment include carnivorous plants such
as pitcher plant and sundew and man-
agers should address the possibility
of threatened and endangered species
in management plans for these areas.
Wildlife using bogs include bog
lemming, four-toed salamander,
spruce grouse, massasauga rattle-
snake, wood frog, moose, spotted
turtle, water shrew, ribbon snake and
neotropical birds such as the olive-
sided flycatcher, northern parula
warbler, bay-breasted warbler and
blackpole warbler.
There is seldom reason to enter the
floating sphagnum mats surrounding
open water portions of bogs and the
best advice is to go around them.
Forested bog peatlands tend to occur
in areas such as Minnesota, Michigan
and Maine where the ground freezes
during the winter months. Manage-
ment activities on the forested areas
should be restricted to periods when
the surface is sufficiently frozen to
support harvesting and other equip-
ment and should utilize the Best
Management Practices listed for
frozen conditions.
A Spotted turtle, Clemmys guttata, likes slow water ~ Northern parula warbler, Parula americana, finds
and numerous insects common in bogs. lichen, Usnea, nesting material, in bogs.
~ Fluctuating water tables can cause wetlands to shift back and forth from Discharging to Recharging.
ground at the base of steep slopes. Vernal
ponds often occur in these areas, but are an
exception in that groundwater flow to and
from vernal ponds is practically nil in the
northeast. Mountain top swamps are often re-
charging wetlands with groundwater out-
flows to a water table much lower in eleva-
tion.
Inflow water reaches the wetland from
precipitation, surface flow, subsurface flow
and groundwater flow. Surface flow in-
cludes surface runoff, stream-flow and
flood waters. Flood waters can carry
nutrient laden sediments to forested
floodplains where these sediments are
RECHARGING WETLAND
In recharging wetlands, water moves from the wetland into the groundwater
DISCHARGING WETLAND
In discharging wetlands, water moves from groundwater into the wetland
I
5
-------
Fens
The feature that distinguishes fens
from bogs is the fact that fens receive
water from the surrounding watershed
in inflowing streams and groundwater,
while bogs receive water primarily
from precipitation. Fens, therefore, re-
flect the chemistry of the geological
formations through which these waters
flow. In limestone areas the water is
high in calcium carbonate resulting in
fens that are typically buffered to a
near neutral pH of 7. However, the
level of calcium or magnesium bicar-
bonate varies widely in fens. At low
levels of bicarbonate the pH may be
closer to pH 4.6 resulting in an acid
~ Bogs receive water primarily from precipitation with realtively little water from surface flows and discharge only to groundwater.
Resulting organic accumulations contribute to their acidity.
Outflow primarily
to groundwater
~ Wetlands are often connected with outflows of one becoming the inflows of the next. The water supply to the lower wetland is
often delayed until the upper one fills.
deposited making the soil very fertile. For-
ested floodplains can be very productive.
Outflow leaves the wetland by evapora-
tion, transpiration, surface flow, subsur-
face flow or groundwater flow. Evaporation
is water given off to the atmosphere as
water vapor. Transpiration is the process
whereby water taken up by plant roots is
released as vapor to the atmosphere from
the plant leaves. Surface flows out of wet-
lands can be small or large and are often
the origin point of streams. Wetlands are
often connected, to a degree, with surface
and groundwater outflows of one wetland
supplying the inflows to other wetlands
lower in the watershed. The water supply to
the lower wetland can be delayed until the
upper wetland fills to a point where addi-
tional water runs off. As a result, some wet-
lands will not be as well supplied as others
in dry periods.
As stated previously, the water storage
capacity of the wetland is affected by the
soil, the groundwater level and the surface
contour. Wetlands generally occur in
natural depressions in the landscape
where geologic or soil layers restrict
drainage. The surface contours act to col-
lect precipitation and runoff water and
feed it to the depressed area. Groundwa-
ter recharge can take place if the soil is
not already saturated and the surface
contours of the basin hold the water in
place long enough for it to percolate into
the soil. In many cases the shape of the
basin is such that it can be rapidly filled
16
-------
fen. At very high levels of bicarbon-
ate, the water may reach a pH of 9.
Thus, there is much variation among
fens with respect to acidity and they
often do not have the extreme acid
conditions associated with bogs.
The common features of both bogs
and fens are that they accumulate peat
and occur in similar climatic and
physiographic regions. Indeed, they
often occur side by side, one grading
into the other. Under the right condi-
tions, peat can accumulate in low
domes that effectively separate rain
water in the dome from calcium rich
groundwater in the underlying fen.
FENS
Surface f/(
Subsurface
~ Fens receive both surface and subsurface water and have both surface and subsurface outflows. As a result, fens tend to reflect the
chemistry of the underlying geology and can be quite alkaline when fed from limestone sources.
FLOOD STORAGE
A Flood protection is often the re-
sult of topographic features of
the wetland which cause it to fill
rapidly at high flows but release
water slowly during lower flows.
~ A hydrograph shows the volume and timing of flows at a given point in a
watershed.
by precipitation or flood waters and the
water slowly released by a restricted sur-
face outlet, by slowly permeable soil or by
geologic conditions.
The water storage capacity of the wet-
land determines the volume and timing of
water reaching the stream from precipita-
tion. The precipitation reaches the stream
in the form of groundwater or surface runoff
to contribute to streamflow discharge. A
hydrograph is a graph of the volume and
timing of streamflow discharge measured
at a certain point in the watershed. The
hydrograph shows the lapse time, the
amount of time between the onset of pre-
cipitation and the peak stormflow dis-
Storm flow
Basefjo^
T i i i i i i i i i i i i i i i i i i i i i i i i i i
TIME (hrs.)
Center of
IT
rainstorm
HYDROGRAPH
Peak flow rate
17
-------
Leatherleaf, an acid loving plant, often forms
floating rings around the edges of ponds.
ing species occurring as scattered in-
clusions on hummocks. The species
composition of acid fens is similar to
bogs and includes black spruce,
Virginia pine, tamarack, willow, birch,
orchids, leatherleaf and random
sphagnum mats.
As noted previously, many fens are
acidic. However, fens receiving water
from limestone or calcium carbonate
The plant community of the fen is bogs, sedges tend to be more plentiful
more varied than that of a bog and in fens. Typical cool, wet climate
while heaths are more plentiful in vegetation is common with acid lov-
The open areas of Bear Meadows, a poor fen in Central Pennsylvania,
support a lush growth of leatherleaf, Chamaedaphne calyculata, and
highbush blueberry, Vaccinium corymbosum.
charge. It also depicts the volume and dis-
tribution of the stormflow discharge over
time. Wetlands tend to have longer re-
sponse times and lower peak stormflows
distributed over longer time periods. Urban
and developed lands tend to have short
response times and high volume, short
duration stormflow discharges. The overall
effect is that watersheds with wetlands
tend to store and distribute stormflows
over longer time periods resulting in lower
levels of streamflow and reduced probabil-
ity of flooding.
The Natural Valley Storage Project, a
1976 study by the U.S. Army Corps of En-
gineers (COE) concluded that retaining
8,500 acres of wetlands in the Charles
River Basin near Boston, Massachusetts
could prevent flood damages estimated at
$6,000,000 for a single hurricane event.
Projected into perpetuity the value of such
protection is enormous. Based on this
study, the COE opted to purchase the
wetlands for $7,300,000 in lieu of building
a $30,000,000 flood control structure
(Thibodeau and Ostro 1981).
Loss of floodplain forested wetlands
and confinement by levees have reduced
the floodwater storage capacity of the Mis-
sissippi by 80 percent increasing dramati-
cally the potential for flood damage
(Gosselink et al. 1981) The 1993 flood
proved this prediction to be true and re-
sulted in immeasurable damage. Vet gov-
ernments are allowing and even assisting
the rebuilding of some of these same
levees fostering potentially more damage
in the future instead of promoting land use
change to restore the wetlands and re-
duce the potential for future damage.
CHARLES RIVER
AT CHARLES RIVER VILLAGE, MA
I 1 91 C.M.S
18 19 20 21 22 23 24 25
AUGUST, 1955
After Thibodeau and Ostro 1981
~ Peak flow for the Charles River watershed is much lower than peak flow for the
Blackstone, a similar watershed with fewer remaining wetlands.
479 C.M.S
BLACKSTONE RIVER AT NORTHBRIDGE, MA
CO
s
o
Q
Z
o
o
ID
(/)
cc
566
453
340
226
113
0
NATURAL VALLEY STORAGE PROJECT
18
-------
A Spreading globeflower, Trollius laxus, favors
more alkaline wetlands.
geologic sources are much less acidic.
These calcareous fens support a group
of plants that differs somewhat from
the group of plants found in acid fens.
The calcareous fens tend to he
dominated by grasses and sedges as
well as calcium loving trees such as
northern-white cedar and Atlantic
white cedar instead of the sphagnum
moss common to acid fens.
~ The dam in the upper portion of this photo verifies beaver use of fens. Sparse
vegetation marks the alkaline seepage around the perimeter.
Some species of wildlife such as shrub layer for aestivation, or
bog turtles are more common in summer hibernation, particularly in
calcareous fens where they use the the northeast.
""Exaggerated
Peaks
WITHOUT WETLANDS
Hydrologic Buffering
~ Wetlands within a watershed reduce flooding by desynchronizing peak flows.
19
-------
~ Bog turtles, Clemmys muhlenbergii, tend to favor the habitat A Palm warbler, Dendroica palmarum, breeds and feeds in
conditions surrounding calcareous fens for summer aestivation. the low bushes common in fens.
Wildlife species groups associated
with acidic fens are similar to those
associated with bogs. They include
species such as the bog lemming,
four-toed salamander, spruce grouse,
wood frog, moose, spotted turtle, wa-
ter shrew and ribbon snake and
neotropical birds such as the northern
waterthrush and palm warbler.
Because surface outflows trigger
their damming instinct, beaver will
occasionally occupy fens when more
desirable habitat is unavailable.
The tea colored surface outflow
from fens, while not trophy trout wa-
ter, provides important habitat for
small, newly hatched brook trout. The
trout survive because the organic
acids that impart color to the water
also tend to congeal soluble forms of
aluminum which could otherwise be
toxic to trout, particularly young trout.
Trout in these streams have been
observed to survive spring "acid
shock" loading when trout in nearby
clear streams have not survived.
Europeans refer to peatlands, both
SOILS
One of the identifying characteristics of
wetlands, from both ecological and statu-
tory points of view, is the presence of hy-
dric, or wet, soils. Hydric soils are defined
by the U.S.D.A. Natural Resources Conser-
vation Service (NRCS) as "soils that
formed under conditions of saturation,
flooding or ponding long enough during the
growing season to develop anaerobic con-
ditions in the upper part."
The three critical factors that must exist
for the soil to be classified as hydric soil
are saturation, reduction and redoxi-
morphic features. When a dominant por-
tion of the soil exhibits these three ele-
ments the soil is classified a hydric soil.
Saturation, the first factor, occurs when
enough water is present to limit the diffu-
sion of air into the soil. When the soil is
~ Dull gray general soil background, or matrix color, and bright red-orange iron
concentrations, or mottles, indicate a fluctuating water table.
saturated for extended periods of time a
layer of decomposing organic matter accu-
mulates at the soil surface.
Reduction, the second factor, occurs
when the soil is virtually free of elemental
oxygen. Under these conditions soil mi-
crobes must substitute oxygen-containing
iron compounds in their respiratory pro-
cess or cease their decomposition of or-
ganic matter.
20
-------
~ Grasses, Gramineae, dominate the alkaline
portions of this fen.
A Showy ladyslipper, Cypripedium reginae, favors
more alkaline wetlands.
bogs and fens, with the word "mire"
which says a lot about operating in
these areas. Machinery can be "mired
down" unless operations are con-
ducted under frozen conditions.
These areas, by virtue of the condi-
tions necessary for their existence, are
rarely dry, so operating in a dry sea-
son is all but impossible.
Redoximorphic features, the third fac-
tor, include gray layers and gray mottles
both of which occur when iron compounds
are reduced by soil microbes in anaerobic
soils. Iron, in its reduced form, is mobile
and can be carried in the groundwater so-
lution. When the iron and its brown color
are thus removed, the soils show the gray
color of their sand particles. The anaero-
bic, reduced zones can be recognized by
their gray, blue, or blue-gray color. The
mobilized iron tends to collect in aerobic
zones within the soil where it oxidizes, or
combines with additional oxygen, to form
splotches of bright red-orange color called
mottles. The mottles are most prevalent in
the zones of fluctuating water and thus
help mark the seasonal high water table.
The blue-gray layer with mottling gener-
ally describes wetland mineral soils. How-
ever, where saturation is prolonged, the
slowed decomposition rate results in the
formation of a dark organic layer over the
top of the blue-gray mineral layer.
Although classification criteria are some-
what complex, soils with less than 20
percent organic matter are generally
classified as mineral soils and soils with
more than 20 percent organic matter are
classified as organic soils. For the
purposes of this document, the organic
layer becomes important when it reaches
a thickness of approximately 16 inches.
Under the right conditions, the layer can
grow to many feet in thickness.
The organic soils are separated in the
soil survey into Fibrists, Saprists, and
Hemists. The Fibrists, or peat soils, con-
sist of soils in which the layer is brown to
black color with most of the decomposing
plant material still recognizable. In
Saprists, or muck soils, the layer is black
colored and the plant materials are de-
composed beyond recognition. The mucks
are black and greasy when moist and al-
most liquid when wet. Mucks have few
discernible fibers when rubbed between
the fingers and will stain the hands. The
Hemists, mucky peats, are in between in
both color and degree of decomposition.
Identification of larger areas of hydric
soil has been simplified. They are identi-
fied on maps available at USDA Natural
Resources Conservation Service (NRCS)
county offices.
The amount and decomposition of the
organic component determines several
important differences between mineral
and organic wetland soils.
~ Organic soils are characterized by
very dark color and either fibrous or
gelatinous structure.
21
-------
60
¦n
¦L '>;
^§ ft 1 '¦
SB Hk
I
#1 Hydric Soil
O = incompletely decomposed organic debris
A = black muck in surface
C = recently trapped sediment
AB = buried surface or original soil
Profile #1 is a hydric soil and the wettest of the
soils in this photo series. It shows two hydric soil
characteristics, a thickened organic layer,
explained below, and a gray matrix explained
under the second profile. Profile #1 occurs at the
lowest point in the wetland and is inundated for
extended periods of time. The ponded water fills
the soil pores preventing air from entering the
soil. A few days of soil saturation is usually
sufficienl for soil microbes to exhaust the supply
of dissolved oxygen in the soil water. The lack of
oxygen slows the process of microbial decomposi-
tion causing partially decomposed organic matter
to accumulate above the mineral layers of soil
creating the thickened O and A layers apparent in
this soil profile. The thick organic layer al the soil
surface indicates a hydric soil.
50+.
O = decaying organic debris
A = very dark gray organic matter
incorporated into mineral surface
B = zone of fluctuating water table gray
matrix with many strong brown iron
concentrations.
C = zone of extended periods of saturation,
gray matrix with few strong brown iron
concentrations.
Profile #2, also a hydric soil, is somewhat higher in
the landscape and although still subject to
fluctuating water tables and lengthy periods of
saturation, is not inundated for long periods.
Therefore, the soil shows the gray matrix color in
the B and C layers, but not the thickened organic
surface. Without oxygen, microbes must utilize
iron compounds to obtain energy from organic
matter. In the process, iron compounds are
converted from insoluble to soluble and (lushed out
leaving the gray background color. As iron
precipitates in the aerated zones, additional soluble
iron migrates from anaerobic sites unitl they
become so depleted of iron that the gray color
predominates. The term matrix is used to describe
conditions in the dominant volume of soil within a
layer. A soil layer is considered to be anaerobic
when the soil matrix is dominated by gray
depiction color. Layers B and C show the gray
matrix indicating that these layers are saturated for
long periods. The dull gray matrix extending to the
soil surface indicates a hydric soil.
#3 Hydric Soil
() = organic debris
A = very dark grayish brown organic
accumulations in surface.
AB = dark gray matrix and strong brown iron
concentrations.
B = dark gray matrix with light gray
depletions and strong brown iron
concentrations.
Profile #3 is also a hydric soil and although
saturated for shorter periods of time, still shows
the strong gray matrix color all the way to the soil
surface. Fluctuating water levels in the soil allow
air to fill the larger pores as the water level lowers
and then trap the air as the water level rises again.
When ihe iron dissolved in the water encounters a
zone of trapped air, it forms a strong red-brown
colored precipitale. The precipitated colors are
known as concentrations or mottles and are
evident here in the AB and B layers. The gray
matrix with bright mottles extending to very near
the soil surface indicates a hydric soil.
22
-------
Length (Meter)
<) = leaf fragments over humus
A = very dark grayish brown organic matter
in surface.
AB = light olive brown matrix with grayish
brown depletions and strong brown iron
concentrations
B = light yellowish brown matrix with gray
depictions and yellowish brown iron
concentrations.
Profile #4 is significantly higher in the landscape
and though it weakly displays wetness
characteristics it is not a hydric soil. In both the
A and B layers the matrix has medium colors
associated with the original evenly distributed
oxidized iron coatings on sand grains. Small
areas of iron depletion and concentration exist,
however the segregation process and attendant
gray color is not dominant in any layer. This soil
is probably saturated to the surface for only very
short periods of time and is, therefore, not a
hydric soil.
O = leaf fragments
A = very dark grayish brown organic matter
in surface.
AB = olive brown matrix with olive yellow iron
concentrations.
K = light olive brown matrix with pale brown
depletions and yellowish brown iron
concentrations.
Profile #5 is not a hydric soil and shows evidence of
saturation only in the deeper layers of the soil. As
stated previously, iron depletions and concentrations
are evidence of iron segregation due to saturation.
The AB layer is saturated and anaerobic so
infrequently that gray depletions are almost
nonexistent. The deeper B layer shows faint
depletions indicating that the soil is saturated only at
depth and only for relatively short periods. Since
the soil is seldom saturated to the surface and only
saturated at depth for short periods of time, it is not
a hydric soil.
() = leaf fragments
A = very dark grayish brown organic matter
in surface.
AH = olive brown subsurface.
B = yellowish brown subsoil.
Profile #6 occupying the highest landscape
position in this series, shows essentially no
evidence of saturation and is not a hydric soil. In
this soil the vertical redistribution of iron into
horizons is associated with water percolating
down through the soil profile. As a result, iron is
evenly distributed within each of the soil layers.
Saturation is either absent or restricted to such
brief periods that the soil does not develop
anaerobic conditions, thus preventing iron
segregation and development of the gray matrix
within the soil horizons. The absence of
inundation also prevents the development of
organic accumulations on the surface.
23
-------
Mineral Soil
Wetlands
Headwater Wetlands
Headwater wetlands are temporarily
to seasonally Hooded wetlands located
at the origins of streams. Headwater
wetlands have a hydroperiod that is
characterized by predictable flooding
associated with spring runoff and spo-
radic flooding associated with
localized storm events. Headwater
wetlands tend to be discharge wetlands
where soil water and groundwater sur-
face to become the origin of streams.
Thus, these systems are hydrologically
open and soluble inorganic material in
groundwater plus soluble organic ma-
terial in surface outflow are flushed
causing headwater wetlands to be less
acidic and more fertile than bogs and
fens. The hydroperiod for headwater
~ Black spruce, Picea mariana, and cinnamon fern, Osmunda cinnamomea, help iden-
tify this headwater wetland during a dry Pennsylvania summer
Organic soils have lower bulk densi-
ties, that is lower weight per unit of vol-
ume, than mineral soils. Consequently,
organic soils have more pore space and
greater water holding capacity and while
flooded can be more than 80 percent wa-
ter by volume. By contrast, mineral soils
are usually less than 55 percent water.
However, water holding capacity has
little effect on flood storage because the
pores are usually filled and do not readily
release moisture from the less porous
lower layers.
The hydraulic conductivity, a measure
of the speed at which water can move
through the soil, varies considerably both
within and between organic and mineral
soils. While organic soils may have a
larger water storage capacity, water
movement may be considerably slower
than in mineral soils. Much depends on
the degree of decomposition of organic
matter. However, the effect tends to ex-
tend the response time or period of time
between the onset of a storm event and
the resulting peak streamflow as dis-
cussed in the hydrology section.
Decomposition is also important in de-
termining the location of the levels of
greatest flow with respect to the surface
in organic soils. The chart by Boelter
and Verry shows that more than 90 per-
cent of the horizontal water flow in or-
ganic soil wetlands occurs at a depth of
less than 12 inches below the surface.
Relatively undecomposed organic mat-
ter near the surface creates larger pore
spaces permitting greater flows. As depth in-
creases and organic matter is more com-
pletely decomposed, pore spaces are
blocked by ever finer particles of organic mat-
ter and flow is reduced.
HORIZONTAL WATER FLOW RATE
AS A FUNCTION OF DEPTH BELOW THE SURFACE IN WETLANDS
Soil Horizon
(inches below
the surface)
Horizontal
Water Flow
Rate
(inches per hour)
Reduction
In
Flow Rate
(percent)
Degree of
Decomposition
(1 to 10)
0-3
250
0
1
3-6
140
44
2
6-9
63
75
3
9-12
21
92
4
12 - 18
7
97
5
18 - 24
3
99
6 & 7
Boelter and Verry 1977
24
-------
A The northern dusky salamander, Des-
mognathus luscus, a good swimmer,
climber and burrower, is well suited to
headwater wetlands.
wetlands shows spring time flooding
as well as additional frequent flood-
ing associated with even small local
storms.
Common vegetation in headwater
wetlands includes red maple, black
gum, sweet gum, ash, swamp white
oak. loblolly pine, nettles, and jewel-
weed.
A The shy, elusive mourning warbler,
Oporornis Philadelphia, favors moist
thickets of headwater wetlands.
Wildlife inhabiting the headwater
wetlands include spring salamander,
wood turtle, water shrew, common
merganser, northern dusky sala-
mander, two-lined salamander, beaver
and moose and neotropical birds such
as the Louisiana waterthrush and
mourning warbler.
Landings and equipment storage
~ Spotted touch-me-not, or jewelweed,
Impatiens capensis, is a common plant
in headwater wetlands
areas should be kept out of headwater
wetlands due to the frequent, unpre-
dictable flooding common to these
wetlands. Open hydrologic condi-
tions mean extra care since pollutants
introduced here can quickly affect
downstream environments.
Organic soils tend to be richer than mineral
soils in the nutrients important to plant pro-
ductivity. But organic soils often have very low
productivity because the nutrients present are
bound in organic compounds and thus un-
available for plant growth. Therefore, unless
the wetland receives an inflow of nutrients
from other sources, the plant forms present
are apt to be those with low nutrient require-
ments or special adaptations such as carnivo-
rous plants.
When not flooded, organic soils generally
have more hydrogen cations available, tending
to make them more acid than mineral soils.
Hence, acid loving plants are associated with
organic soils. An example is the sphagnum
mat or ring that forms around a bog lake. Ex-
ceptions are those fens which are influenced
by limestone geology and thus receive cal-
cium bicarbonate in groundwater. The bicar-
bonate easily removes the free hydrogen cat-
ions by forming water and carbon dioxide and
results in fens that are neutral to basic.
Organic soils have a greater potential for
removal of excess nutrients and other pollut-
ants. Small soil particles with large surface to
volume ratios have the ability to attract and
hold positively charged ions, known as cat-
ions, such as ammonium (NH/) and calcium
(CA"). The cations are adsorbed or loosely
held by electrical attraction. Cations held in
this way may be stored for extended peri-
ods in sediments or removed and incorpo-
rated into other natural compounds by
chemical or microbial activity. When the
adsorbed cations are incorporated into
other compounds the soil particles become
available to adsorb additional cations. In
this way, wetland soils maintain their ability
to remove and recycle excess nutrients and
other pollutants. Cation exchange capacity
is one measure of the potential for wetland
soils to alter the chemistry of the waters
moving through them and to transform nu-
trients into other forms.
-------
Streamside Wetlands
Streamside wetlands may be nar-
row in upland areas and expand some-
what as the valleys widen along larger
streams. Because these wetlands are
associated with streams having larger
watersheds, the hydroperiod has a
more predictable pattern in which
flooding is closely associated with
spring thaw and larger, more regional-
ized storm events. Hydrographs for
streamside wetlands also show some
delay between storm events and peak
flows due to the distance from the
headwaters. Like headwater wetlands,
streamside wetlands are hydrologi-
cally open.
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In summer, the status of this Massachusetts streamside wetland is indicated
only by subtle vegetative hints.
VEGETATION
Another of the physical characteristics
used to identify wetlands is the presence
of hydrophytic vegetation. The term hy-
drophyte comes from the Greek words
hydro, meaning water, and phyton,
meaning plant. The term hydrophyte in-
cludes all aquatic and wetland plants.
However, the term is generally used to
refer to vascular aquatic and wetland
plants. Though hydrophytes represent
only a small percentage of the total plant
population, there are far too many to list
here.
Upland plants normally have ad-
equate soil oxygen available to the roots
for use in the metabolic processes that
convert food into energy. When soil satu-
ration or flooding make oxygen unavail-
able, the metabolic process either stops
altogether or shifts to anaerobic glycoly-
sis, an enzymatic process that does not
require oxygen to convert food into en-
ergy. Anaerobic glycosis produces much
less energy than normal metabolic pro-
cesses and causes an accumulation of
toxic end products. Using anaerobic
glycosis, most plants can produce only
enough food to survive for short periods
~ Hypertrophied lenticels, horizontal swollen areas on the base of this silver maple tree,
facilitate exchange of oxygen between the tree tissue and the atmosphere.
of time. Hydrophytic plants thrive in wet-
land soils in spite of the limitation or ab-
sence of oxygen because they are able to
make special physiological adaptations.
Hydrophytic plants vary in the number
of adaptations they exhibit, but generally
those that exhibit a greater number of ad-
aptations also exhibit greater tolerance to
saturated soil conditions. Relatively few
tree species, such as cypress and water
tupelo, are able to make enough of these
adaptations to tolerate flooding for more
than a few weeks during the growing sea-
son. However, there are a number of spe-
cies that exhibit one or more of these ad-
aptations and thus tolerate varying degrees
26
-------
The greatest variety of plant and
animal species in the forest are
associated with streamside wetlands.
Vegetation associated with these wet-
lands include ostrich fern, sycamore,
red maple, swamp white oak, green
ash, river birch, black willow, privet,
speckled alder and pin oak.
~ Springtime floods remove all doubts as to the status of the streamside wetland seen
in the picture at left.
~ Alligator weed, Alternanthera philoxe-
roides: stem cross-sections show pro-
gressively larger aerenchyma forma-
tions from the drier site (upper left) to
the wettest site sample (lower right).
An oxygenated rhizosphere or coloration of
the exterior root surface caused by oxidizing
of iron by air leaking out of the roots into oth-
erwise anaerobic soil.
~ A pore lining: the dark circle surrounding
the opening is caused by oxidizing of iron
by air reaching otherwise anaerobic soil
through the pore opening.
of soil wetness. Some plants such as
green ash form hypertrophied lenticels,
enlarged structures on the above ground
portion of the plant that permit the ex-
change of gasses with the atmosphere fa-
cilitating the transfer of oxygen from the air
to the plant tissue. Green ash and north-
ern white-cedar grow large diameter, suc-
culent roots at least partially composed of
cells with air spaces between them, called
aerenchyma, which facilitate movement of
oxygen throughout the root tissue. Water
hickory, black spruce and balsam fir de-
velop fibrous, lateral root systems which
tend to spread horizontally above the wet-
ter soil levels. Larch, water hickory and
water tupelo develop adventitious roots,
extra roots on the tree stem, again, above
the level of the wetter soil. Bald cypress
and water tupelo develop a swelling at the
base of the tree which helps resist
windthrow and may facilitate the exchange
of oxygen.
In some wetland adapted plants such
as cordgrass, Spartina, the oxygen supply
is large enough to cause oxygen to be dif-
fused out through the roots oxygenating
the rhizosphere, or outer surface of the
root. Soil iron and manganese deposits in
these areas are often oxidized by this
method resulting in streaks of rust com-
monly seen in wetland soils.
27
-------
Hydrophytic and other plants used to gate Upland (UPL, < 1 percent occur-
identify wetlands for regulatory purposes rence in wetlands in the area in question,
are listed in the National List of Plant Spe- but may be wetland plants in other re-
cies that Occur in Wetlands, (Reed, 1988). gions). Abundant presence of species in
This publication lists five indicator catego- the Obligate and Facultative Wetland indi-
ries for plants which can be found in wet- cator categories is a reliable indicator that
lands: Obligate Wetland (OBL, > 99 per- a given tract of land is functionally a wet-
cent occurrence), Facultative Wetland land. The absence of these species,
(FACW, 67-98 percent occurrence), Facul- however, is not a reliable indicator that an
tative (FAC, 37-67 percent occurrence), area is not a wetland, as these species
Facultative Upland (FACU, found in wet- may have been locally extirpated by se-
lands 1-33 percent of the time), and Obli- vere disturbance or management.
~ Royal fern, Osmunda regalis
Common cattail, Typha latifolia A New York ironweed, Vemonia noveboracensis
-------
The following is a list of some plants
that commonly occur in wetlands in the
Northeastern Area along with their indica-
tor category for the northeastern region.
This is not a comprehensive list, but
merely a short list of readily identified
plants the presence of which may indicate
the need for further reconnaissance to de-
termine if wetlands are present in the
area. To be effective, a short list would
have to be developed for a specific locale.
Common Name
swamp white oak
northern white-cedar
green ash
black spruce
tamarack
water tupelo
highbush cranberry
small cranberry
leatherleaf
buttonbush
swamp azalea
winterberry
speckled alder
swamp privet
swamp rosemallow
royal fern
sensitive fern
common cattail
soft-stem bulrush
wool-grass
skunk-cabbage
round-leaved sundew
pitcher plant
American burreed
common arrowhead
common reed
purple loosestrife
cardinal flower
New York ironweed
alligator weed
Botanical Name
Quercus bicolor
Thuja occidentalis
Fraxinus pennsylvanica
Picea mariana
Larix laricina
Nyssa aquatica
Vaccinium trilobum
Vaccinium oxycoccos
Chamaedaphne calyculata
Cephalanthus occidentalis
Rhododendron viscosum
Ilex verticillata
Alnus rugosa
Forestiera acuminata
Hibiscus moscheutos
Osmunda regalis
Onoclea sensibilis
Typha latifolia
Scirpus validus
Scirpus cyperinus
Symplocarpus foetidus
Drosera rotundifolia
Sarracenia purpurea
Sparganium americanum
Sagittaria latifolia
Phragmites australis
Lythrum salicaria
Lobelia cardinalis
Vernonia noveboracensis
Alternanthera philoxeroides
Category
FACW
FACW
FACW
FACW
FACW
OBL
FACW
OBL
OBL
OBL
OBL
FACW
FACW
OBL
OBL
OBL
FACW
OBL
OBL
FACW
OBL
OBL
OBL
OBL
OBL
FACW
FACW
FACW
FACW
OBL
~ The spikes of sensitive or bead fern,
Onoclea sensibilis, persist through
the winter.
American burreed, Sparganium americanum A Sensitive fern, Onoclea sensibilis
29
-------
A Speckled alder, Alnus rugosa, a common shrub in streamside wetlands, is readily
recognized by its catkins, or seed heads.
Streamside wetlands provide
habitat for the two-lined salamander,
green frog, bullfrog, pickerel frog,
leopard frog, musk turtle, wood
turtle, box turtle, snapping turtle,
muskrat, mink, otter, moose, great
blue heron, green heron, black duck,
wood duck, red-breasted merganser,
kingfisher, woodcock, osprey and bald
eagle. These also provide important
BIOGEOCHEMICAL
CYCLES
The basic elements that occur in living
organisms move through the environment
in a series of naturally occurring physical,
chemical and biological processes known
as biogeochemical cycles. The cycle gen-
erally describes the physical state, chemi-
cal form, and biogeochemical processes
affecting the substance at each point in
the cycle in an undisturbed ecosystem.
Many of these processes are influenced
by microbial populations that are naturally
adapted to life in either aerobic, oxygen-
ated, or anaerobic, oxygen free, condi-
tions. Because both of these conditions
are readily created by varied and fluctuat-
ing water levels, wetlands support a
greater variety of these processes than
other ecosystems.
There is usually a physical state,
chemical form, and location in the cycle in
which nature stores the bulk of the various
chemical elements. Pollution occurs when
the cycle is sufficiently disturbed that an
element is caused to accumulate at some
point in the cycle in an inappropriate
physical state, chemical form, location or
amount disrupting environmental balance.
In the nitrogen
cycle, for example,
the bulk nitrogen is
stored as nitrogen gas in
the atmosphere.The nitro-
gen cycling process in wet-
lands involves both aerobic
and anaerobic conditions. Nitro-
gen in the form of ammonium
(NH4) is released from decaying plant and
animal matter under both aerobic and
anaerobic conditions in a process known
as ammonification. The ammonium then
moves to the aerobic layer where it is con-
verted to nitrate (N03). Nitrate not taken
up by plants or immobilized by adsorption
onto soil particles can leach downward
with percolating water to reach the
groundwater supply or move with surface
and subsurface flow. Nitrate can also
move back to the anaerobic layer where it
may be converted to nitrogen gas by deni-
trification, a bacterial process, and sub-
sequently returned to the atmosphere.
If both aerobic and anaerobic condi-
tions were not available, some of the cycle
processes would cease and pollutants
could accumulate. In wetlands, anaerobic
conditions are amply provided by flooding
and by saturated soils. However, the oxy-
gen requiring processes take place in a
thin oxidized zone usually existing at the
soil surface. This layer may be only a frac-
tion of an inch thick and is present even
when the wetland is submerged. In many
wetlands the water table fluctuates 12 to
18 inches each year with the summer level
averaging between 4 and 18 inches below
the surface of the soil. This zone of aera-
tion is often called the active layer or in
Russian soil terminology, where it was first
used, the acrotelm.
Phosphorus, sulfur, iron, manganese
and carbon also move through the wetland
ecosystem in complex cycles. Sulfur and
30
-------
habitat for neotropical birds such as the
yellow warbler, yellow-throated war-
bler and eastern phoebe.
While flooding is somewhat more
predictable in streamside wetlands than
in headwater wetlands, they are still
subject to occasional unexpected flood-
ing. This, along with the relatively
~ Box turtle, Terrapene Carolina, burrows in
the mud ot streamside wetlands to stay
cool in summer.
~ Yellow warbler, Dendroica petechia, builds a nest of silver-gray
fibers in low bushes of streamside wetlands, often adding new
floors to avoid hatching eggs of invading cowbirds.
small area involved, makes it prudent to locate
landings and equipment storage areas outside
of these wetlands. When it is absolutely neces-
sary for haul roads and skid trails to be located
in the wetland, they must be designed so as not
to impede the natural hydrology including the
inflow and outflow of flood waters.
nh3
gasification
fixation
plankton
nh3
Organic N —» ~~ NH4
Oxygenated
Soil i
uyw.
y$yS^S^^^66666ib6m
~ NO
After Mitsch and Gosselink 1993
Nitrogen cycling in wetlands progresses more rapidly where there is a thin
oxygenated soil layer present.
carbon, like nitrogen, have gaseous cycles.
As a result of the biogeochemical cycle
processes, sulfides and methane are re-
leased into the atmosphere attended by the
smell of rotten eggs and swamp gas re-
spectively. Phosphorus, however, has a
sediment cycle with excess phosphorus
being tied up in sediments, peat in organic
wetlands and clay particles in mineral wet-
lands. However, although phosphorus re-
tention is an important attribute of wet-
lands, sediment attached phosphorus is
subject to resuspension and movement
with water when sediments are disturbed.
The cycles are similar in that they pro-
vide storage for excess elements and re-
quire a certain amount of time to complete
the chemical processes. The cycle pro-
cesses also require the varying environ-
ments provided by aerobic and anaerobic
conditions. In closed systems, the pro-
cesses take place within the wetland. In
open systems, like riparian wetlands,
many elements can be imported from or
exported to adjacent systems with surface
and groundwater flows or flooding.
To avoid changing the natural bio-
geochemical function, it is important that
the hydrology of the wetland, the inflow,
outflow and residence time of the water,
remain relatively undisturbed. It is also
necessary to minimize disturbance to the
aerobic zone of saturated soils. However,
even with minimal disturbance, wetlands
will continue to function as net receptors
(sinks) or net exporters (sources) of vari-
ous elements primarily due to seasonal
and other natural fluctuations in the bio-
geochemical cycle processes.
31
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Wooded Swamps
Wooded swamps include broad
bottomland forests in the floodplains
of large rivers with very large water-
sheds. As a result, the hydroperiod
shows a very predictable pattern in
which flooding is associated only with
spring thaw and prolonged, regional
storm events. Hydrographs for
wooded swamps show greater delay
between storm events and peak flows
due to the remoteness of their head-
waters. Wooded swamps are also hy-
drologically open and dependent, to a
degree, on floodwaters for the deliv-
ery of nutrient laden silts affecting
their fertility.
Red maple, Acer rubrum, is a common species
in wooded swamps such as Beckviile Woods
in Indiana.
WILDLIFE
Forested wetlands generally support a
greater variety of wildlife than nearby up-
land forests. Wetlands are essential life
support systems to a tremendous array of
wildlife species. The variety of forested
wetland types and the associated varia-
tion in plant communities provide all of
the essential habitat needs for species
such as the wood turtle, massasauga,
water shrew, muskrat, beaver and various
ducks, geese and herons. Wetlands also
provide one or more essential habitat
needs for many other species such as
the tree swallow, yellow warbler, alder fly-
catcher, star nose mole and woodcock.
Manipulation of wetland wildlife habitat
or alteration of wildlife populations
through management practices may be
detrimental to wildlife. Alternatively, forest
management practices can accomplish
many wildlife objectives if conducted with
consideration given to the principles of
sound wildlife management. Objectives
may be enhancing wildlife diversity or
habitat, preventing destruction of habitat,
providing for consumptive or non-con-
One third of all bird species, such as these snow geese, Chen hyperborea, depend
on wetlands for one or more of their habitat requirements.
sumptive use of wildlife or managing for a waterfowl and, nationwide, all wild ducks,
particular endangered or threatened spe- geese, swans, herons and bitterns require
cies habitat. wetlands, vernal ponds or spring seeps for
Wetlands are most often identified with reproduction activities. The central flyway,
32
-------
A Cinnamon fern, Osmunda cinnamomea, helps identify wooded swamps
in summer, while the fertile spikes in the center of the fern remain as a
clue throughout the winter.
~ Wooded swamps supply the snakes,
frogs and small birds that constitute
the diet of the red-shouldered hawk,
Buteo lineatus.
a corridor composed of takes, streams and
wetlands scattered in a north-south direc-
tion through the central U.S., is used by
millions of ducks and geese for their annual
A Black bear, Ursus americanus, spend
more than 60 percent of their lives
in wetlands.
migrations because of the resting opportu-
nities it provides. Waterfowl habitat needs
change with the season, stage of life and
type of waterfowl, yet the various kinds of
wetlands provide for all of these habitat re-
quirements. Wood ducks, for example, find
their habitat needs in forested wetlands.
In addition, one third of all U.S. bird spe-
cies, about 230 out of 686 species, de-
pend on wetlands for one or more of their
life requirements. As an example, the tree
swallow, while not totally dependent on
wetlands, is dependent on wetlands for
both nesting and feeding habitat. The red
shouldered hawk prefers beaver ponds for
feeding areas and the woodcock makes
heavy use of alder thickets to search for
summer earthworms.
Wetlands are important to mammals as
a source of food and cover. Bears are
omnivorous consumers and feed on fish,
frogs and numerous berries found in wet-
lands. Bears are known to spend 60 per-
cent of their time in spring and summer in
forested wetlands and the remainder of
their time moving between wetland areas
(Newton 1988). Mink favor cover found in
thickets in forested wetlands. White-tailed
deer, beaver and weasel are examples of
species that also utilize cover and food
available in wetlands.
The rich food supply of microscopic al-
gae and small invertebrates and the lack
of predatory fish in vernal pools provides a
• • m.
;>W|)c ****»;.
• i se-
mom ¦'
,i , y '' '/ '
33
-------
~ Skunk cabbage, Symplocarpus foetidus, appears
in early spring and grows so rapidly that heat of
respiration helps it melt its way through the snow.
Vegetation includes ostrich fern,
royal fern, cinnamon fern, Canada
mayflower, goldthread, starry false
Solomon's seal, nodding trillium,
American false-hellebore, lizard's
tail, skunk cabbage, red maple, bald
cypress, pin oak, swamp white oak.
swamp chestnut oak, overcup oak,
willow oak, cherrybark oak, black
gum, water tupelo, swamp tupelo, Cot-
tonwood, sycamore, loblolly pine and
Atlantic white cedar.
Wooded swamps provide habitat
for wood duck, hooded merganser,
spotted turtle, star-nosed mole, mink,
raccoon, water snake, ribbon snake,
~ False hellebore, Veratrum viride, is a
conspicuous spring wetland plant.
wood frog, spring peeper, gray treefrog,
spotted salamander, great blue heron,
green heron, barred owl and neotropical
birds such as the northern waterthrush,
habitat significant and sometimes critical
to the continued survival of amphibians.
Approximately 190 species of amphibians,
including frogs, toads and salamanders,
require wetlands such as vernal pools or
spring seeps for reproduction activities.
Some of these habitat requirements are
unusual and very specific. The four-toed
salamander makes its nest in the sides of
sphagnum hummocks in such a way that
the newly hatched salamanders fall di-
rectly into water, a condition critical to their
survival. However, many other reptiles and
amphibians have simply adapted to the
fluctuating water levels commonly found in
wetland environments.
Most freshwater fish feed in wetlands
or on wetland produced foods. Wetlands
in the flood plains of larger rivers provide
spawning habitat for species such as bull-
head, yellow perch, northern pike and
muskellunge and are critical to the contin-
ued survival of these species. Yellow
perch, walleye and bluegills leave open
lake waters to spawn in shallow water
wetlands.
Most commercial game fish use
coastal wetlands as spawning and as
nursery grounds. Striped bass, bluefish,
salmon, menhaden and flounder are
~ This moose, Alces alces, a common wetland dweller, is just emerging
with a lunch of aquatic plants.
among the species of fish that depend on
coastal wetlands. Shellfish such as oys-
ters, clams, shrimp and blue crabs also
depend on coastal wetlands for survival.
Although wetlands comprise only about
5 percent of the land area of the 48 con-
tiguous states, almost 35 percent of the
nation's threatened and endangered spe-
cies either live in or depend on wetlands.
Canby's dropwort is an example of an en-
dangered plant species found in herba-
ceous wetlands in Maryland.
34
-------
~ American redstart, Setophaga ruticilla,
is the only warbler with large orange to
yellow tail patches.
common yellowthroat, blue-gray gnat-
catcher and American redstart.
Because wooded swamps tend to be
larger in land area, it may be necessary
to locate some skid trails, landings or
haul roads within them. These facili-
ties should be held to the absolute
minimum and constructed during the
Large blueflag, Iris versicolor, oc-
curs in swamps from Maine to Ten-
nessee. The word "flag" is from the
Middle English "flagge," meaning
rush or reed.
predictable dry periods. Skid trails,
landings and haul roads must also be
designed so as not to impede the
natural hydrology including the in-
flow and outflow of flood waters.
aquatic habitat by slowing water move-
ment and allowing sediment to settle out
of the water column. Wetlands provide
special protective cover for some species
such as the special winter cover provided
to pheasants by cattails.
Additional indirect benefits wetlands
provide to wildlife include drinking water
sites, special feeding sites and
travelways. Special feeding sites are best
characterized by spring seeps, the broad,
very shallow water wetlands that provide
the first snow free areas in early spring
and are heavily used for feeding by wild
turkeys. Wooded wetlands along large
streams in otherwise open country are
used as travelways by migrating
neotropical birds and large mammals
such as bear, deer and moose when trav-
eling between larger tracts of forest.
In northern states where prolonged
winters are combined with deep snows,
the population of large ungulates such as
deer and moose is directly dependent on
the quality and quantity of the vegetation
in the wooded wetlands of the region.
Wetlands with overstory conifers for ther-
mal cover and a dense understory for a
food source are used by deer throughout
the winter.
~ Coniferous wetland deer yarding areas provide relief from cold weather
and deep snow.
ceous wetlands in Maryland.
Besides the direct habitat benefits pro-
vided to wetland dependent fish and wild-
life species, wetlands also provide sub-
stantial indirect benefits to wildlife. Wet-
lands improve water quality for fish and
wildlife by serving as nutrient sinks. Wet-
lands tend to reduce coliform levels as a
result of prolonged exposure of the bacte-
ria to sunlight, oxygen and cool water
temperatures in the slow moving waters
of colder wetlands. Wetlands improve
35
-------
~ A spring seep on Twin Branch, Monongahela National Forest, West Virginia,
shows the broad shallow character of the flow.
Spring Seeps
Spring seeps are broad shallow
flows that occur where groundwater
emerges on sloping terrain usually on
the lower slopes of hillsides and
mountains. They are discharging wet-
lands in these situations and can be
the source of small streams. However,
they may also percolate back into the
groundwater becoming recharging
wetlands.
Spring seeps are valuable to wild-
life, particularly wild turkey, in severe
winters because the emerging ground-
water provides snow free feeding sites
in winter and are among the first sites
to provide green plants in spring.
~ Wild turkey, Meleagris gallopavo, use spring seeps for snow-free foraging
in early spring.
36
-------
B • tiy '&¦ ¦
¦j*:* G&m&s
Viiw. 'is*
MMM
[?*.<>•¦!:': £•-<'
A A spring seep on the Allegheny National Forest in Pennsylvania; ferns and mosses mark
the broad shallow seep area.
Spring seeps are used by amphibians
such as the northern dusky salamander,
spring salamander and by neotropical
birds such as the worm eating warbler,
veery and wood thrush.
Plants to look for include moist site
tree species, skunk cabbage, sedges,
water cress, marsh marigold, goldthread,
wintergreen and sensitive fern.
Where possible, haul roads and skid
trails should be routed above the seep at a
distance sufficient to avoid disturbing the
flow. When roads or trails must pass be-
low the seep they should pass at a point
beyond where the seep has reentered the
ground or where a defined channel
permits an environmentally acceptable
crossing such as a culvert.
~ Wood thrush, Hylocichla muslelina, the only thrush with a bright
reddish-brown head, has an unhurried, bell-like melody. It builds
a nest of mud and grass in low shrubs.
37
-------
Beaver Ponds
Beaver respond to an instinct to
impound flowing water. Conse-
quently, beaver ponds usually expand
and alter existing streamside wet-
lands. However, beaver also create
ponds and wetlands where none
would otherwise exist. Beaver pond
ecosystems have their own life cycle.
Trees and other vegetation are killed
by the prolonged high water levels un-
til little more than grasses and forbs
remain. In time, the beaver's food
supply will be depleted resulting in
abandonment of the dam, lowering of
the water table and a return to forest
through plant succession. Once for-
ested, the cycle starts over with bea-
ver re-establishment. The hydrology
of the wetland created by a beaver
dam reflects the hydrology of the set-
ting in which it is built. If the beaver
dam is built in a headwater setting,
the hydrology will be similar to that
of a headwater wetland.
Many forest plants and animals
depend on the site at different stages
>>r.**
"I
v'i
fSl; i -v v.
JL
Q
t/)
~ Beaver dam wetlands provide special habitat needs of other species such as great blue heron.
Note a tree top nest in the center background.
38
-------
in the cycle. Snags, large old dead
trees, left in the pond from the forest
cycle provide preferred nesting sites
for herons and nesting cavity species.
Hence both forest and pond cycles
are necessary to sustain this habitat.
Plants typical of beaver pond wet-
lands include pondweed, arrowhead,
cattail, smartweed, alder, red maple,
aspen, manna grass, rice cutgrass,
bulrushes and sedges.
~ Beaver, Castor canadensis, will often abandon their dams when preferred food
species are depleted.
~ Abandoned beaver dams provide a series of unique habitats as they progress through
various successive stages on their return to forest conditions.
39
-------
Wildlife species using beaver dam
wetlands include beaver, great blue
heron, green heron, red spotted newt,
green frog, bullfrog, wood duck,
black duck, hooded merganser, snap-
ping turtle, water snake, ribbon snake,
star nosed mole, mink, otter, moose,
tree swallow, raccoon, spring peeper,
gray treefrog, bullfrog. Neotropical
birds such as the prothonatory
warbler, Philadelphia vireo, tree
swallow and ruby crowned kinglet
also use beaver ponds.
~ Great blue heron, Ardea herodias, the largest of the herons, approaches
48 inches tall and builds nests of twigs in swamps and on ridges
overlooking broad rivers. It can often be seen in wetlands where it
stands motionless for long periods, fishing.
~ The tree swallow, Iridoprocne bicolor,
is the hardiest of the swallows and
the only eastern/midwestern swallow
with all white underparts. It nests in
cavities or boxes near water.
Regulatory requirements vary from
state to state. Check with your state
fish and game department before
disturbing a beaver pond. Bridging
the narrow stream below the dam may
be the best alternative for crossing
drainages with beaver dams.
~ The great blue heron flies with slow, heavy wingbeats,
appearing almost prehistoric.
40
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Vernal Ponds
Vernal ponds are small ponds that
are most obvious in the forest during
the spring of the year. Although some
vernal ponds may not meet the statu-
tory definition of wetlands, they will
be addressed here because the subject
comes up whenever wetland forest
management is discussed. The ponds
derive their name from vernalis, the
Latin word for spring, because they
result from various combinations of
snowmelt, precipitation and high wa-
ter tables associated with the spring
season. The ponds tend to occur in
small depressions and while many
dry up in late summer, a few have
water year round. The ponds vary
greatly in terms of recharge, dis-
charge characteristics, source of
water and geology. Those supplied by
groundwater from limestone geology
tend to be less acid and less variable
in acidity. By definition, vernal ponds
are free of fish and can, therefore,
support a rich community of amphib-
ians and invertebrates that would be
difficult to sustain if fish were
present.
~ Vernal ponds should be located in late winter or early spring when the ponds are most readily recognized.
Salamander activity is at its peak at this time.
41
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~ The marbled salamander, Ambystoma opacum, mates and males deposit
sperm sacks (at right of head) on warm, rainy summer nights.
Typical pond users include salamanders such
as the marbled salamander which migrates from
burrows in the forest floor to the pond basin with
the onset of fall rains. The males leave sperm
sacks to be used by the females to fertilize the
eggs which are deposited under rocks and leaves
on the pond bottom. The adults then return to the
forest and as the fall rains fill the pond the eggs
hatch and the larvae feed on the invertebrate life
of the pond. The Jefferson salamander migrates
over the snow on rainy nights in late winter to
slip into the pond through cracks in the ice. After
mating, the females attach their egg masses to
small twigs under water. The spotted salamander
arrives after the Jefferson and similarly deposits
egg masses on twigs under the water.
~ The female marbled salamanders
fertilize and deposit their eggs
a few days after mating.
Jefferson salamanders, ^
Ambystoma jeffersonianum,
migrate through the icy pond
surface on late winter nights
when temperatures are a
degree or two above freezing
and light rain is falling to mate
in pairs and deposit eggs on
twigs in the pond.
42
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<4 Spotted salamanders,
Ambystoma maculatum,
mate in groups shortly after
the Jefferson salamanders
and also attach their eggs to
twigs where they will swell to
large gelatinous masses.
These species are followed in turn
by wood frogs, spring peepers, spade-
foot toads, gray tree frogs, American
toads and other amphibians that
depend on the pond habitat for repro-
duction. The developing amphibians
prey on fairy shrimp, copepods,
daphnia, phantom midge larvae, and
mosquito larvae and, in turn, are
preyed upon by insect predators such
as diving beetles, backswimmers and
fishflies (Cassell 1993). Neotropical
birds such as the worm eating war-
bler, veery and wood thrush also use
the vernal pond area.
In the months that follow, wood frogs, Rana sylvatica, and
other amphibians visit the ponds to lay eggs.
~ These fairy shrimp and other pond life provide food
for the voracious young salamanders.
The ponds typically occur under the
forest canopy with the pond basin rela-
tively free of vegetation. Thinning of the
canopy can result in accelerated evapora-
tion rates shortening the duration of pond
flooding and dehydrating the larvae be-
fore development is complete. Increased
exposure to sunlight can also result in in-
vasion of the pond by rice cutgrass,
manna grass, sedges and buttonbush
which appear to be more favorable to
species such as green frogs, pickerel
frogs and cricket frogs which are not
typical of canopied ponds.
-------
~ Buttonbush, Cephalanthus occidentalis
A Vernal ponds are difficult to recognize in summer, but buttressed trees, blackened
leaves and water-stained trunks are clues.
Deep tire ruts in the vicinity of the
pond are also a problem. They can be
a physical trap for young sala-
manders and turtles not developed
enough to climb out of them. The
ruts can also be mistaken for the
pond destination by adults who
deposit egg masses in the ruts. In
both cases, the young will probably
be eaten by predators or die of
dehydration because the ruts usually
dry out before the vernal ponds.
The ponds are easily recognized
in early spring when they are filled
with water and this is the best time to
establish their location. In summer
they are more difficult to recognize,
but some indicators are blackened
and compressed leaf litter, buttressed
tree trunks, water marked tree trunks,
and the presence of vegetation such
as red maple, highbush blueberry and
buttonbush.
Management plans should call for
marking the location of vernal ponds
and any necessary protective zones in
the spring when the ponds are filled
with water.
A Crown closure must be maintained over the pond to prevent destruction of
the habitat by the invasion of buttonbush and other undesirable plants.
44
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Wetlands
Best Management
Practices
Table of Contents
Three Primary Considerations 46
Planning 46
Access Systems
Permanent Haul Roads 47
Road construction on soils with organic layers
in excess of 16 inches in thickness 48
Road construction on soils with organic layers
in excess of 4 feet in thickness 48
Road construction on soils with organic layers
between 1.3 and 4 feet in thickness 49
Road construction on mineral soils or those with surface
organic layers less then 1.3 feet in thickness 50
Temporary Road Construction On All Soils 51
Skid Trails 52
Landings 54
Maintenance Areas 55
Logging Under Frozen Conditions 55
Streamsides And Stream Crossings 55
Felling Practices 56
Silviculture 56
Wildlife And Fish
General Considerations 56
Within a 50 foot wide wildlife management zone
around wetlands 58
Within a 150 foot wide wildlife management zone
around wetlands 59
Spring Seeps 59
Vernal Ponds 60
Legal Requirements 61
Where To Go For Assistance 62
45
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WETLANDS
BEST MANAGEMENT PRACTICES
The following is a list of wetland best management practices intended to supplement
existing upland forestry best management practices and to reduce potential adverse
impacts of forest management activities on wetlands. Note that some upland BMP's have
been included as appropriate to facilitate understanding. While some of the practices may
be required by law, they are listed here simply as a means of protecting the wetlands func-
tions and values.
This list is intended as an example and to be effective should be supplemented or
refined by individual State Foresters in consultation with representatives of other
natural resource management agencies such as the U.S. Army Corps of Engineers,
Environmental Protection Agency, Natural Resources Conservation Service, Fish
and Wildlife Service, State Water Quality Agency, consultant foresters, forest
industry representatives and others for use in their respective states. The list should
not be considered a checklist of mandatory practices as there will seldom be a situa-
tion in which all of the practices will be needed on the same area at the same time.
THREE PRIMARY CONSIDERATIONS
1.
Consider the relative importance of the wetland in relation
to the total property to be managed. Perhaps the wetland
should simply be left undisturbed.
2.
Protect the environment. Do not alter the hydrology of the
wetland by:
¦ All of the BMP's
in this document
¦ restricting the inflow or outflow of surface,
sub-surface or groundwater,
¦ reducing residence time of waters,
can be traced
back to these
¦ introducing toxic substances,
three primary
¦ changing the temperature regime.
considerations.
3.
Protect wildlife habitat to the extent that knowledge per-
mits and to a level consistent with its value to society.
PLANNING
Identify and comply with federal, state, and local laws and regulations as discussed
in the legal requirements section of this document.
Identify control points: those places within the area to be managed that should be ac-
cessed, those that should be avoided or those that need special consideration.
Some examples of control points are:
• Location of surface water, spring seeps and other wetlands.
Note that these are best located in the spring as many wetlands
are difficult to identify during dry periods.
• Location of environmentally preferable stream crossing points.
• Location of streamside management zones as described below.
• Location of areas requiring special equipment or timing of operations.
46
-------
The timber sale contract or harvest agreement should contain language to require the
use of the BMP's identified as necessary in the planning process.
Establish streamside management zones, strips of land bordering surface waters and
in which management activities are adjusted to protect or enhance riparian and
aquatic values. An example would be a strip managed for shade or larger trees to
help maintain cooler water temperatures or provide large woody debris to streams
respectively.
Establish filter strips, strips of land bordering surface waters, that are sufficient in
width based on slope and roughness factors and on which machine access is con-
trolled to prevent sedimentation of surface water.
Locate access system components such as roads, landings, skid trails, and mainte-
nance areas outside of filter strips and streamside management zones.
To eliminate unnecessary soil disturbance, plan the most efficient access system to
serve the entire property, then build only what is currently necessary.
Limit equipment entry into wetlands to the minimum necessary. Avoid equipment
entry into wetlands whenever possible.
ACCESS SYSTEMS
Examples of BMP's presented in the Haul Roads section are based on BMP's being pre-
pared by the Minnesota Department of Natural Resources, Division of Forestry and the
Minnesota Wetland BMP Committee.
PERMANENT HAUL ROADS
Haul roads are travelways over which logs are moved while fully supported on the
bed of a wheeled truck.
Timber haul costs include construction, hauling and maintenance of both roads and
equipment. Use of poor practices to reduce construction costs only results in related
increases in hauling and maintenance costs. A properly located and constructed road
will be most cost efficient and will have limited adverse impact on water resources
including wetlands and aquatic and riparian habitats.
Consider threatened and endangered species habitat, trout spawning seasons, and
public water supplies when locating and building roads.
Avoid constructing roads through wetlands unless there are no reasonable alterna-
tives.
Where roads must be constructed through wetlands, use the following and other
BMP's to design and construct the road system so as neither to create permanent
changes in wetland water levels nor alter the wetland drainage patterns.
Road drainage designs in wetlands must provide cross drainage of the wetland dur-
ing both flooded and low water conditions.
Avoid road construction and use during spring thaw and other wet periods.
Use drainage techniques such as crowning, insloping, outsloping and 2 percent
minimum grades as well as surface gravel and maintenance to ensure adequate
drainage and discourage rutting and associated erosion and sedimentation.
Divert outflow from road drainage ditches prior to entering wetlands and riparian
areas to minimize the introduction of sediment and other pollutants into these sensi-
tive areas.
Minimize the width of the road running surface to the minimum necessary to safely
meet owners objectives, typically 12 feet wide for straight sections and 16 feet wide
for curves. Additional width may need to be cleared of large vegetation to accom-
modate plowed snow.
47
-------
Cease road use if ruts exceed 6 inches in depth for more than 300 feet.
Consider use of geotextile fabric during construction to minimize disturbance, fill
requirements, and maintenance costs.
All fills in wetlands should be constructed of free draining granular material.
Road construction on soils with organic layers in excess
of 16 inches in thickness
Organic soils vary greatly in strength, and consultation with a registered engineer is
advised when designing roads on these soils.
Permanent haul roads built on organic wetlands must provide for cross drainage of
water on the surface and in the top 12 inches of soil. This can be accomplished
through the incorporation of culverts or porous layers at appropriate levels in the
road fill to pass water at its normal level through the road corridor.
my////////A
All culverts in organic soils should be 24 inch diameter and placed with their bottom
half in the upper 12 inches of the soil to handle the subsurface flow and their top
half above the surface to handle above ground flow. Failure to provide drainage in
the top 12 inches of the soil can result in changes in the hydrology of the wetland
and subsequent changes in water chemistry and plant and animal habitat.
Road construction on soils with organic layers in excess
of 4 feet in thickness
Where organic soils are greater than 4 feet deep, the road should be constructed
across the top of the soil surface by placing fill material on top of geotextile fabric
and/or log corduroy. The road will sink into the peat somewhat due to its weight and
the low bearing strength of the soil and will require cross drainage to prevent inter-
ruption of the wetland flow.
POROUS ROAD DESIGN
Wetland
Surface
Road
Surface
The 12 inch layer of porous material
is placed to align in elevation with the
porous soil layer
48
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~ Geotextile is then placed on top of the corduroy
along with a layer of wood chunks to form the
porous layer. Coarse gravel could be substituted.
~ Another layer of geotextile is placed on top of the
chunkwood to prevent contamination and sealing of
the porous layer. The gravel running surface is placed
on top of the geotextile fabric.
~ A permeable section road being
constructed by first laying
geotextile fabric.
~ A corduroy of parallel laying logs is
placed on top of the geotextile.
Road construction on soils with organic layers between 1.3 and
4 feet in thickness
§
Where organic soils are less than 4 feet deep, fill can be placed directly on the peat
| surface and allowed to sink compressing or displacing the peat until equilibrium is
reached. With this method, culverts are used instead of porous layers to move sur-
z face and subsurface flows through the road fill material.
"o
Culverts should be placed at the lowest elevation on the road centerline with addi-
tional culverts as needed to provide adequate cross drainage.
Q>
O
Ditches parallel to the road centerline should be constructed along the toe of the fill
to collect surface and subsurface water, carry it through the culvert and redistribute
^ it on the other side.
One method of drainage is to incorporate a 12 inch thick layer of porous material
such as large stone or chunkwood into the roadbed. This material should be sepa-
rated from the adjacent fill layers by geotextile fabric, and be incorporated into the
road fill design so as to lie in the top 12 inches of the soil thus providing a continu-
ous cross drainage.
Climate permitting, construction on soils with deep organic layers is best undertaken
when the organic soil is frozen in order to preserve the strength of the root mat.
Where continuous porous layers are not used, culverts should be placed at points
where they will receive the greatest support from the soil below. These areas gener-
ally occur near the edge of the wetlands or as inclusions where the organic soil is
shallow.
Ditches parallel to the roadbed on both sides should be used to collect surface and
subsurface water, carry it through the culvert and redistribute it on the other side.
These ditches should be located three times the depth of the organic layer from the
edge of the road fill unless otherwise determined by an engineer.
Earth Fill
Chunkwood
ALTERNATIVE POROUS ROAD DESIGN
(shown in photo sequence below)
¦10'
Log Corduroy
Lightweight nonwoven
Geotextile
-------
Road Construction on Mineral Soils or Those with Surface
Organic Layers Less than 1.3 Feet in Thickness
Roads through mineral soil wetlands can be constructed using normal road construc-
tion techniques. Use geotextiles to increase bearing strength of the road and to pre-
serve the bearing strength of fill material by preventing contamination with fine soil
particles.
In mineral soil wetlands, a culvert should be placed at the lowest elevation on the
road centerline with additional culverts as needed to provide adequate cross drain-
age.
Ditches parallel to the road centerline should be constructed along the toe of the fill
to collect surface and subsurface water, carry it through the culvert and redistribute
it on the other side.
Fills should be constructed of free draining granular material.
CULVERT LOCATION FOR ROADS ON MINERAL SOIL
AND SHALLOW ORGANIC SOIL WETLANDS
plan view
I 1 DITCH | 1
1 — 1
ROAD ,
DITCH
section AA'
24 inch diameter culverts should be installed with the lower half in the porous upper 12 inch
layer of organic soil to accommodate drainage during normal and inundated conditions.
~ Wooden mats are an efficient solution to
temporary road access and can be carried
and placed by a log truck.
~ A mat road to a log landing
in Maryland
2 FOOT DIAMETER
cross section
>A
road surface
-------
O
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SKID TRAILS
Skid trails are rough travelways for logging machinery. Logs are often dragged over
the skid trail surface only partially supported by the machine pulling them and par-
tially supported on the trail surface.
Avoid equipment entry into wetlands especially those that can be logged by cable
from adjoining uplands.
Where equipment entry into wetlands is unavoidable, minimize the area disturbed as
well as the number of repeated passes over the same trail.
Ruts over 6 inches in depth can block normal subsurface drainage and create sur-
face channels resulting in either a raised water table or shorter residence time and
excessive drainage. Do not create a pattern of trails with 6 inch ruts that either
blocks or facilitates drainage.
Use low ground pressure equipment when possible or tracked vehicles on both or-
ganic soil wetlands and mineral soil wetlands where soils have greater than 18 per-
cent fines as defined by the Natural Resources Conservation Service. Use conven-
tional tires on skidders only when the ground is dry or frozen.
K
High floatation equipment such as these extra wide
tires helps to prevent rutting.
~ Track vehicles with elevated pans also limit rutting.
This track vehicle fells and bunches trees, reducing the
density of the skid trail pattern.
Note the difference in rutting between wide tire (left) and
conventional tires (right) in the same skidding situation.
52
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Use of high flotation tires on areas that are marginally operable with conventional
equipment results in minimal impact. Use of high flotation tires to extend opera-
tions into areas that could not be operated with conventional equipment can result
in adverse impacts.
Schedule the harvest during the drier seasons of the year or during time when the
ground is frozen. Consider ceasing operations in areas where rutting exceeds 6
inches in depth.
Prepare skid trails for anticipated traffic and weather conditions including spring
thaws to facilitate drainage and avoid unnecessary rutting, relocation and washouts.
Minimize the crossing of perennial or intermittent streams and waterways. Use por-
table bridges, poled fords and corduroy approaches or other mitigating measures to
prevent channel and bank disturbance and sedimentation.
Cross streams at right angles and use bumper trees to keep logs on the trail or
bridge and off the stream banks.
Do not skid through vernal ponds, spring seeps, or stream channels.
Use brush or corduroy to minimize soil compaction and rutting when skidding in
wet areas.
Reduce skid volumes when skidding through wetland areas.
~ This smaller feller/buncher uses a
track system over rubber tires for
versatility.
The staggered-end design of this low-cost
portable skidder bridge, built by John
Conkey Logging Co., helps to keep it
in position in use.
The skidder bridge is ^
strong enough to carry
the skidder without
intermediate support.
~
The skidder bridge consists of two sections, permitting it to
be carried and placed by the skidder that will use it.
53
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TitfWitf* is
~ Several ramps can be used
together to extend the length
of the crossing.
Corduroy approaches help to control ~ These skidder ramps are lighter weight and
erosion and keep mud off the logs will sometimes require logs for support,
and out of the stream.
LANDINGS
Keep the number and size of landings to the minimum necessary to accommodate
the area, the products harvested and the equipment necessary to the activity pre-
scribed.
Where possible, locate landings outside wetlands and far from streams on well
drained areas with gentle grades where drainage into and away from the landing can
be controlled. These practices will minimize soil compaction as well as soil erosion
and sedimentation of surface waters that can result from concentrated heavy equip-
ment use.
~ This is an excellent landing located on a well-drained area immediately
adjoining the wetland.
If no other locations are practical, place landings on the highest ground possible
within the wetland and use them under dry or frozen conditions only.
Geotextile fabric use at landing sites is recommended in wetlands and on soils with
low bearing strength to minimize soil erosion and compaction.
Geotextile fabric is difficult to impractical to remove when covered with gravel or
fill. Where removal is required consider the use of wood or metal platforms or mats
with or without geotextiles as necessary.
Consult with Federal, State and local authorities regarding permit requirements be-
fore using fill or pads for landings located in wetlands.
-------
MAINTENANCE AREAS
Locate maintenance areas to avoid the spillage of oil, fuel and other hazardous ma-
terials into wetlands. Store operating supplies of such materials away from wetlands.
Designate a specific location for draining lubricants and other fluids during routine
maintenance. Provide for collection, storage and proper disposal.
Provide containers to collect fluids when the inevitable breakdown occurs in the
wetland and repairs must be made on the site.
LOGGING UNDER FROZEN CONDITIONS
Avoid crossing springs, seeps and areas of water which do not freeze well.
Where water crossings cannot be avoided or frozen conditions cannot be relied
upon, use portable bridges or poled fords. Temporary structures are preferable to
permanent ones unless the crossing is on a permanent road.
Design the crossing to save the structure and accommodate high flows in the event
of an untimely thaw.
Plow or pack snow in the operating area to minimize the insulation value and facili-
tate ground freezing. Clear enough area to accommodate future snow plowing.
Monitor the operating conditions closely after three consecutive nights of above
freezing temperatures or the occurrence of warm rain. Cease operations when ruts
exceed 6 inches in depth.When daytime temperatures are above freezing, but night-
time temperatures remain below freezing, plan to operate only in the morning and
cease operations when rutting begins.
Plan to move equipment and materials to upland areas prior to the occurrence of
thawing conditions.
STREAMSIDES AND STREAM CROSSINGS
Streamside Management Zones (SMZ's) are strips of land which border surface wa-
ters and in which management activities are adjusted to protect or enhance riparian
and aquatic values. The width of SMZ's varies with the intended purpose. An ex-
ample would be a strip managed for shade or larger trees to help maintain cooler
water temperatures or provide large woody debris to streams.
Filter Strips are strips of land bordering surface waters and sufficient in width, based
on slope and roughness factors, to prevent soil erosion and sedimentation of surface
water.
Establish a streamside management zone with a minimum width equivalent to one
and one half tree heights between heavy harvest cuts such as clearcuts or seed tree
cuts and permanent and intermittent streams to prevent nutrient leaching into
streams.
Establish a streamside management zone on perennial and intermittent streams.
Maintain 50 percent crown cover to limit water and ground surface temperature in-
creases. Manage for older trees at the water's edge to provide a natural supply of
large woody debris and to shade the water surface. The necessary width of the zone
will vary with climate and stream direction. SMZ's should normally be one and one
half tree heights in width, however, due to sun position, a 15 foot width may be all
that is necessary on the north side of east-west running stream sections in northern
latitudes.
Within the streamside management zone, maximize cable lengths and minimize the
number and length of skid trails to reduce canopy and ground disturbance.
55
-------
Establish filter strips on lands adjacent to lakes and streams using the following
guide to control erosion and sedimentation of surface waters.
Percent slope
Recommended width of filter strip
(slope distance in feet)
25
0 - 1
2-10
11-20
21 - 40
41 - 70
30 - 50
50 - 70
70-110
110 - 170
Roads and trails should be minimized in streamside management zones, but should
be located outside of the filter strips except where stream crossing is necessary.
Naturally occurring woody debris should be allowed to remain in streams. However,
avoid felling trees into streams and remove from the streams any tree tops and other
slash resulting from the logging operation. In some cases, potential damage to the
channel and bank will outweigh the need for removal.
Precautions should be taken when logging near a wetland or stream. Felling trees
into water bodies can cause habitat damage and disturb breeding and spawning areas
of amphibious and aquatic species. However, naturally occurring woody debris is
necessary to many stream functions and should be left undisturbed.
Avoid felling trees into nonforested wetlands. When such felling is unavoidable,
remove the tree to high ground before limbing. Slash from trees felled on upland
sites is considered fill material under the Clean Water Act and may not be deposited
on wetland sites.
Keep slash resulting from the logging operation out of streams and wetlands with
standing water unless specifically prescribed for fish or wildlife habitat purposes.
Normally, slash left in these areas uses oxygen needed by fish and other aquatic
animals. Slash can also limit access of certain species to wetlands.
Review the section on vernal pools and temporary ponds for exceptions to these
guidelines.
Distribute the size, timing and spacing of regeneration cuts, including clearcuts, to
minimize changes in ground surface and water temperature over the wetland as a
whole. Maintain a crown cover of 50 percent or more during selection and thinning
cuts. Exceptions may occur in very cold climates where low water temperatures are
a habitat limitation.
On organic soils, conduct site preparation operations such as shearing and raking
only when the ground is sufficiently frozen to avoid machinery breaking through the
root mat.
Do not deposit slash and other residues from upland operations in wetlands.
Timber activities in forested wetlands should be avoided during the breeding period
of threatened and endangered fish and wildlife species known to inhabit the wetland.
Preserve areas where hummocks of thick sphagnum moss abut small or large pools
of water as a unique habitat combination required by the four-toed salamander.
FELLING PRACTICES
SILVICULTURE
WILDLIFE AND FISH
GENERAL CONSIDERATIONS
56
-------
AW'
A Four-toed salamander, Hemidactylium scutatum
&*
An area of sphagnum humps; a critical nesting habitat
for the four-toed salamander.
In order to survive, four-toed salamander eggs must
be nested so that the newly hatched salamanders will
drop into the water.
~ A wood duck chick about to jump
from a nest box.
Avoid harvesting trees in wetlands April through June to protect breeding birds in-
cluding neotropicals.
Leave as many as 15 dead and live nesting cavity trees per acre within 200 feet of
water as nesting sites for wood ducks.
Avoid sedimentation of areas known to support spawning populations of brook trout,
particularly during the October-December spawning season.
Adult male
wood duck,
Aix sponsa,
inhabits
freshwater
marshes,
wooded
swamps and
creeks.
-------
Within a 50 foot wide wildlife management zone
around wetlands
Maintain 50 percent crown cover to avoid wide water and soil temperature fluctua-
tions that can adversely affect fish and aquatic and amphibian habitat.
Leave 5-15 dead standing trees and snags per acre for insect feeding and for nesting
and escape cavities for birds.
Manage for tall trees along the edge of lakes and rivers associated with wetlands to
provide nesting sites for ospreys, eagles, and red-shouldered hawks.
Avoid disturbing rotting stumps where possible as they provide nesting substrate for
musk turtles.
A An osprey, Pandion haliaetus, with young in a typical wetland nest site.
~ The orange ear patch clearly identifies this bog turtle.
Within calcareous fens where chalky, crumbly deposits are evident in surface pools,
preserve and encourage scrub and/or shrub habitat as important over-wintering
habitat for rare bog turtles.
Encourage and preserve herbaceous vegetative cover along wetland edges to pro-
vide shelter for frogs, ribbon snakes, hatching turtles, and small mammals.
Minimize skid trails and/or use cabling to reduce the area of soil compaction thus
preserving habitat for small mammals and turtles.
58
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Within a 150 foot wide wildlife management zone
around wetlands
Avoid routing skid trails through areas with concentrations of physical structure
such as dead logs, hollow logs, upturned roots, rock piles, rock outcrops and other
debris.
~ Structure created by logs and boulders is critical to small amphibian habitat and
disturbance should be avoided.
Minimize skid trail density and heavy equipment use to avoid crushing the many
turtles such as the spotted turtle, wood turtle and Blanding's turtle that either forage
or aestivate (become dormant during the summer) in these areas.
Minimize ruts deeper than 6 inches below general ground level and regrade trails
promptly to prevent trapping of juvenile salamanders and hatchling turtles.
Close logging roads and skid trails to vehicle use after cutting because exposed
areas and pools that form where roads and trails cross wet areas are attractive haz-
ards for turtles.
Avoid clearcutting in favor of harvesting methods that maintain a greater canopy
cover like patch cuts, shelterwood cuts and selection cuts. Where clearcuts are un-
avoidable, cuts should be less than 10 acres in size and narrow and irregular in
shape.
Do not skid through seeps.
Fell trees away from seeps.
Maintain at least 50 percent crown cover in the group of trees shading the seep to
limit increases in water and ground surface temperature.
Avoid disturbing the soil around these areas to minimize sedimentation and distur-
bance of leaf litter.
Where haul roads must cross seeps, locate the haul road at least 150 feet downslope
from the origin of the seep. Also avoid road building within 150 feet upslope from
seeps. Both limitations are intended to protect the origin and continued flow of the
seep.
SPRING SEEPS
59
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VERNAL PONDS
Examples of BMP's presented in the section on Vernal Ponds are based on BMP's
developed by researchers, foresters and wildlife biologists in Massachusetts, Penn-
sylvania and New York. Research is continuing in this area and changes are ex-
pected as more is learned about the importance of vernal ponds.
Vernal ponds provide critical habitat for a number of amphibians and invertebrates,
some of which breed only in these unique ecosystems, and/or may be rare, threat-
ened or endangered species. Although vernal ponds may only hold water for a pe-
riod in the spring, the most important protective measure is learning to recognize
these pond locations, even in the dry season. Foresters can then incorporate the
guidelines below into their plans to ensure that these habitats thrive.
Maintain the physical integrity of the pond depression and its ability to hold sea-
sonal water by keeping heavy equipment out of the pond depression and away from
the perimeter walls at all times of the year. Rutting here could cause the water to
drain too early, stranding amphibian eggs before they hatch. Compaction could al-
ter water flow and harm eggs and/or larvae buried in leaf litter at the bottom of the
depression.
Prevent sedimentation from nearby areas of disturbed soil to prevent disrupting the
pond's breeding environment.
Keep tree tops and slash out of the pond depression. Although amphibians often use
twigs up to an inch in diameter to attach their eggs, none should be added, nor exist-
ing branches removed. If an occasional top does land in the pond depression, leave
it. Removal could disturb newly laid eggs or hatched salamanders.
Establish a buffer zone around the pond two chains (132 feet) in width. Maintain a
minimum of 50 percent crown cover and minimize disturbance of the leaf litter and
mineral soil which insulate the ground and create proper moisture and temperature
conditions for amphibian migrations.
Schedule operations in the buffer area when the ground is frozen and covered with
snow to minimize ground disturbance within the buffer area.
Avoid operating in the buffer area during muddy conditions which would create ruts
deeper than 6 inches. Such ruts can result in trapping and predation of migrating ju-
veniles and dehydration of mistakenly deposited eggs. Ruts should be filled and op-
erations suspended until the ground is dry or frozen.
Locate landings and heavily used skid trails outside of the buffer area. Be sure any
water diversion structures associated with skid trails and roads keep sediment from
entering the shaded zone and the vernal pond.
Silt fences are formidable barriers to salamander migration. Do not use them in the
buffer area and remove them from nearby areas as soon as practicable.
Close roads in the area to prevent off road vehicle disturbance to the pond and sen-
sitive buffer zone.
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LEGAL REQUIREMENTS
Mechanized land clearing and earth moving activities in wetlands, streams or other water
bodies are regulated at the Federal level under Section 404 of the Clean Water Act. Many
states also have regulatory programs which may require permits for activities in streams
and wetlands. An approved forest management plan may be required by your state re-
gardless of whether wetlands are involved or not.
Normal silvicultural activities which may involve earthmoving are exempt from regula-
tion under section 404 of the Clean Water Act. However, to qualify for the exemption, the
activity must be part of an established, ongoing operation. Furthermore, the exemption is
interpreted by some to apply only to silvicultural activities resulting in the production of
food, fiber and forest products. General permits may exist in some Corps of Engineer dis-
tricts which authorize silvicultural activities for other purposes.
Any activity which converts a wetland into a non-wetland or affects the flow, circulation
or reach of waters is not exempt. Conversion into a new use, such as clearing forested
wetlands for pasture, crop land or development, requires a permit as well.
Normal silvicultural practices covered by the silvicultural exemption include planting,
seeding, cultivating, minor drainage and harvesting. However, the silvicultural exemp-
tion does not include land recontouring activities such as grading, land leveling, filling in
low spots or converting to upland. Minor drainage is the connection of upland drainage
facilities to a stream or water body. This does not include any new drainage of wetlands
or the construction of any ditches or dikes which drain or significantly modify a stream or
wetland.
Maintenance of existing drainage ditches, structures and fill is exempt from federal regu-
lation provided there is no modification of the original design. Construction and mainte-
nance of forest roads are exempt if the work is done in accordance with the state ap-
proved Best Management Practices (BMP's).
A Federal permit is not needed to cut trees at or above the stump. However, mechanized
land clearing, excavation, grading, land leveling, windrowing and road construction in
wetlands will require a permit if the activity does not qualify for the silvicultural exemp-
tion.
It is recommended that a determination of any specific permit requirements be obtained
from the district office of the U.S. Army Corps of Engineers as well as the state environ-
mental or natural resources agency prior to initiating any activities in water or wetlands.
This is particularly important in light of the ongoing changes in wetland regulations at
both the state and federal level.
The Food Security Act of 1985 and the Food, Agriculture, Conservation and Trade Act of
1990 contain provisions which could cause loss of U.S.D.A. program benefits to persons
conducting activities which may alter wetlands. Consult with your local U.S.D.A. Con-
solidated Farm Services Agency (formerly Agricultural Stabilization and Conservation
Service) or U.S.D.A. Natural Resources Conservation Service (formerly Soil Conserva-
tion Service) if wetland is present to determine if proposed forest management activities
would jeopardize U.S.D.A. benefits.
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WHERE TO GO FOR ASSISTANCE
Contact the office of the State Forester for assistance in forest management on both up-
lands and wetlands. However, forest management activities on wetlands are subject to
special regulations.
The District Office of the U.S. Army Corps of Engineers has the authority to determine
which lands are subject to wetland regulations. The telephone number is listed in the
"Government Offices" section of the telephone directory, normally under "Army,"
"Department of the Army" or "Department of Defense." Ask for the "Regulatory" or
"Permits" Branch.
The following are the telephone numbers for the Corps of Engineers district offices serv-
ing Virginia and the twenty states of the Northeastern Area.
Baltimore, MD (410) 962-3670
Buffalo, NY (716) 879-4330
Chicago, IL (312)353-8213
Detroit, MI (313)226-2432
Huntington, WV (304) 529-5487
Kansas City, MO (816) 426-3645
Little Rock, AR (501) 324-5295
Louisville, KY (502)582-6461
Memphis, TN (901) 544-3471
Waltham, MA (New England Division) (617) 647-8338
New York, NY (212) 264-3996
Norfolk, VA (804) 441 -7652
Philadelphia, PA (215) 656-6728
Pittsburgh, PA (412) 644-6872
Rock Island, IL (309) 788-6361 ext 6379
St. Louis, MO (314) 331-8575
St. Paul, MN (612) 220-0375
Tulsa, OK (918)581-7261
The County Soil Survey Report will provide an indication of whether your property may
contain any hydric or wetland soils. These surveys are available from the county office of
the U.S.D.A. Natural Resources Conservation Service.
The National Wetland Inventory is another source of information. These maps are
produced by the U.S.D.I. Fish and Wildlife Service and correspond to the U.S.D.I. Geo-
logical Survey quadrangle maps (7.5 x 7.5 minutes). They can be obtained by calling
l-800-USA-MAPS. These maps are very general and should not be used for any regula-
tory purpose, but can provide useful information about areas where wetlands can be ex-
pected to occur. The only way to accurately determine the extent of wetlands on a prop-
erty is to have a qualified individual inspect the property.
Information and photography of indicator and threatened and endangered plants can often
be obtained from local botanical gardens or arboreta, such as the Morris Arboretum of the
University of Pennsylvania as well as environmental centers and natural resource interest
groups such as the Western Pennsylvania Conservancy.
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REFERENCES AND FURTHER READING
Belt, C. B., Jr. 1975. The 1973 flood and man's constriction of the Mississippi River. Science 189:
681-684.
Boelter, D.H.; Verry, E.S. 1977. Peatland and water in the Northern Lake States. General Technical
Report NC-31. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central
Forest Experiment Station; 22 p.
Cassell, R. 1993. The vernal pond, "More than just a mosquito hole." Unpublished drafl supplied
by author.
Cowardin, L.M.; Carter,V.; Golet, F.C.; LaRoe, E.T. 1979. Classification of wetlands and deepwater
habitats of the United States. FWS/OBS-79/31. Washington, DC: U.S. Department of the Interior,
Fish and Wildlife Service; 103 p.
Dahl, T.E. 1990. Wetland losses in the United States, 1780s to 1980s. Washington, DC: U. S. Depart-
ment of the Interior, Fish and Wildlife Service; 21 p.
DeGraff, R.M.; Yamasaki, M.; Leak, W.B.; Lanier, J.W. 1992. New England wildlife: management of
forested habitats. General Technical Report NE-144. Radnor, PA: U.S. Department of Agricul-
ture, Forest Service, Northeastern Forest Experiment Station; 271 p.
Federal Register. 1980. 40 CFR Part 230: Section 404 (b) (1) Guidlines for specification of disposal
sites for dredged or fill material. 45 (249): 85352-85353.
Federal Register. 1982. Title 33: Navigation and navigable waters; Chapter II, Regulatory programs of
the Corps of Engineers, 47 (138): 31810.
Gosselink, J.G.; Conner, W.H.; Day, J.W., Jr.; Turner, R.E. 1981. Classification of wetland resources:
land, timber, and ecology. In: Jackson, B.D.; Chambers, J.L., editors. Timber harvesting in
wetlands. Baton Rouge: Division of Continuing Education; Louisiana State University; 28-48.
Johnson, C.W. 1985. Bogs of the Northeast. Hanover, NH: University Press of New England; 269p.
Larson, J.S.; Newton, R.B. The value of wetlands to people and wildlife. Amherst: U.S. Department of
Agriculture, Cooperative Extension Service, University of Massachusetts; 20 p.
Mason, L. 1990. Portable wetland area and stream crossings. San Dimas, CA: U.S. Department of
Agriculture, Forest Service, Technology Development Center. 110 p.
Mitsch,W.J.;Gosselink,J.G. 1993. Wetlands, 2ded. NewYork: VanNostrand Reinhold Co.; 539 p.
Newton, R.B. 1988. Forested wetlands of the Northeast. Publication No. 88-1. Amherst: University of
Massachusetts, Environmental Institute; 14 p.
Payne, N.F. 1992. Techniques for wildlife habitat management of wetlands. New York: McGraw-Hill
Inc.; 549 p. Reed, P.B. 1988. National list of plant species that occur in wetlands: 1988 national
summary. Biological Report 88 (24). Washington, DC: U.S. Department of the Interior, Fish and
Wildlife Service; 244 p.
Shaw, S.P.; Fredine, C.G. 1956. Wetlands of the United States, Their extent and their value for water-
fowl and other wildlife. Circular 39. Washington, DC: U.S. Department of the Interior, Fish and
Wildlife Service; 67 p.
Thibodeau, F.R.; Ostro, B.D. 1981. An economic analysis of wetlands protection. Journal of Environ-
mental Management 12: 19-30.
Tiner, R.W., Jr. 1987. Mid-Atlantic wetlands, a disappearing natural treasure. Washington, DC: U.S.
Department of the Interior, Fish and Wildlife Service; 28 p.
Tiner, RW.; Kenenski, I.; Nuerminger, T.; Eaton, J.; Foulis, D.B.; Smith, G.S.; Frayer, W.E. 1994. Recent
wetland status and trends in the Chesapeake watershed (1982 to 1989). Technical Report.
Hadley, MA: U.S. Department of the Interior, Fish and Wildlife Service; 70 p.
U.S. Army Corps of Engineers. 1987. Corps of Engineers wetlands delineation manual. Technical
Report Y-87-1. Washington, DC; 100p. + app.
U.S.Department of the Interior, Fish and Wildlife Service. 1990. America's endangered wetlands.
Pamphlet.
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