SWRHL-106r
SOIL SURVEY OF AREA 15
NEVADA TEST SITE
by
Verr D. Leavitt and Benjamin J. Mason
Radiological Research Program
Western Environmental Research Laboratory
ENVIRONMENTAL PROTECTION AGENCY
Published June 1971
This study performed under a Memorandum of
Understanding (No. SF 54 373)
for the
U.S. ATOMIC ENERGY COMMISSION
-------
This report was prepared as an account of work sponsored
by the United States Government. Neither the United
States nor the United States Atomic Energy Commission,
nor any of their employees, nor any of their contractors,
subcontractors, or their employees, makes any warranty,
express or implied, or assumes any legal liability or
responsibility for the accuracy, completeness or useful-
ness of any information, apparatus, product or process
disclosed, or represents that its use would not infringe
privately-owned rights.
Available from the National Technical Information Service,
U. S. Department of Commerce,
Springfield, VA. 22151
Price: paper copy $3.00; microfiche $.95.
01
;>
i~j
-------
SWRHL-106r
SOIL SURVEY OF AREA 15
NEVADA TEST SITE
by
Verr D. Leavitt and Benjamin 0. Mason*
Radiological Research Program
Western Environmental Research Laboratory**
ENVIRONMENTAL PROTECTION AGENCY
Published June 1971
This study performed under a Memorandum of
Understanding (No. SF 54 373)
for the
U.S. ATOMIC ENERGY COMMISSION
* Dr. Benjamin J. Mason, Chief,, Ecology Research Branch, EPA, Bureau of
Air Pollution Sciences, Triangle Park, N.C.
** Formerly Southwestern Radiological Health Laboratory, part of the
U. S. Department of Health, Education, and Welfare, Public Health
Service, Environmental Health Service, Environmental Control
Administration, Bureau of Radiological Health.
-------
ABSTRACT
This report presents the results of a soil survey of the area around the
Environmental Protection Agency Experimental Dairy Farm located in Area 15 of the
U. S. Atomic Energy Commission's Nevada Test Site.
Four soil series were identified. Descriptions of these series are
included along with physical and chemical analyses of representative
samples of the soils.
-------
ACKNOWLEDGEMENTS
The authors would like to express their thanks to Dale D. Moden, Caroline S,
Allen, Eleanor C, Strickland, Ralph F. Smiecinski, Ruby H. Fehler, and
Wallace J. Wipper for their assistance in the chemical analysis of the
soils collected during this survey.
-------
TABLE OF CONTENTS
Page
ABSTRACT i
ACKNOWLEDGMENTS ii
LIST OF TABLE iv
I. INTRODUCTION 1
II. DESCRIPTION OF STUDY AREA 2
A. Study Area 2
B. General Geology 2
C. Climate 3
D. Vegetation 5
E. Chemical Analysis 6
1. Standard Soils Analysis 6
2. Total Chemical Analysis 6
3. Results 7
III. SOIL MAPPING PROCEDURES 8
BIBLIOGRAPHY 21
APPENDICES 22
DISTRIBUTION
m
-------
Page
Table 1. Temperature and Precipitation Data 5
IV
-------
I. INTRODUCTION
The Western Environmental Research Laboratory (WERL), Environmental Protection
Agency (EPA), has maintained an experimental dairy farm on the U. S. Atomic
Energy Commission's Nevada Test Site (NTS) since 1965. The crop area of the
farm is maintained primarily for the production of forage to be used in
experiments conducted by WERL. During controlled releases of radioactivity
at this farm unexplained variations in the levels of retained activity have
appeared. In order to provide information to aid in controlling this
variation the soil survey presented in this report was conducted.
The actual soil survey was conducted in 1966 and the chemical analysis of
samples collected during the survey has been underway since that time.
Soil survey techniques patterned after the Soil Conservation Service's
National Cooperative Soil Survey were used.
-------
II. DESCRIPTION OF STUDY AREA
A. Study Area.
The area surveyed lies in Township 8, South, Range 53 East, in
Area 15 of NTS (see Appendix VI). The boundaries of the study
area are Smoky Hills on the west, Oak Spring Butte on the north,
Rhyolite Hills and Butte Wash on the east, and Sedan Crater on
the south. The total area encompasses approximately 576 acres.
The topography is generally gently-sloping alluvial fans. The
study area occurs at an elevation of 4,500 feet. Much of the
area especially to the north and east occurs on alluvial fans
originating from the Quartzite Mountains and the Rhyolite Hills.
B. Geology.
Most of the soils in the area of this survey have been
developed in sediments that were washed from the surrounding
mountains and laid down by water. Locally, these sediments
were reworked by wind. The remaining soils developed in
residuum that weathered from rocks of the mountains.
The sediments of the survey area were derived mainly from tuff,
quartz, and limestone. A smaller amount of material came from
dolomite, shale, and granite. The dolomite, shale, and quartzite
were interbedded with massive beds of limestone.
The mountains surrounding the survey area consist mainly
of tuffs with smaller areas of limestone, quartz, and other rock.
The tuffs range in depth from surface outcrops to 1,000 feet
below the surface. The tuffs occur in a variety of colors such
as red, yellow, green, brown, gray, and black.
-------
C. Climate.
The WERL dairy farm has a semi-arid, continental climate.
Sunshine is abundant, precipitation is low, the rate of evapora-
tion is high, and the air is dry and clear. In summer the days
are hot but the nights are cool. Winters are fairly cold.
The location of the WERL dairy farm, being in a valley on a plateau
between two major mountain ranges, accounts in large part for the
semi-arid climate. To the west lie the Sierra Nevada, a massive
range of mountains that effectively reduces the moisture content
of storms moving inland from the Pacific Ocean during fall, winter,
and spring. As moist air, in its easterly flow, is forced to
rise over the mountains, it loses much of its moisture on the western
slopes.
The air moving down the eastern slopes is warmed by compression and,
when it reaches the interior valley, is relatively dry. As the air
continues to move eastward each successive mountain range further
reduces the moisture content and is a contributing reason for light
precipitation in Area 15 of the NTS.
The average annual precipitation in this valley is about 5.71 inches.
Of the total yearly precipitation, about 40 percent comes in winter
and early spring, and a large percentage falls during showers and
thunderstorms in July and August. The most rainfall recorded in a
monthly period is 3.69 inches, which fell in January 1969. The
highest annual precipitation reported is 11.43 inches, and the lowest,
2.95 inches.
Snowfall in Area 15 is light, averaging about 12 inches annually. Its
yearly total is rarely more than 2.5 feet, though the maximum annual
snowfall may be as high as three feet.
-------
Table 1. Temperature and Precipitation Data.
Temperature data taken by ESSA at NTS (elevation 4,560 feet) for 3% years,
January 1966 to June 30, 1969. Rainfall measured at Area 15, WERL dairy
farm for 8% years, January 1961 to June 30, 1969.
Temperature
Rainfall
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sept
Oct
Nov
Dec
Aver-*
age
op
40
42
48
53
63
69
75
73
70
60
49
40
Maxi-
mum
°F
64
62
74
75
90
95
96
96
90
81
74
63
Mini-
mum
op
16
21
22
30
37
42
53-
50
49
38
23
16
Aver-*
age
In
0.62
0.70
0.40
0.51
0.19
0.20
0.58
0.74
0.40
0.13
0.54
0.70
Driest
year
(1962)
In
0.23
1.33
0.22
Trace
0.01
0.04
0.20
t
0.55
0.20
Trace
0.17
Wettest
year
(1965)
In
0.11
0.01
1.14
3.15
0.16
0.15
0.39
0.98
t
+
2.66
2.68
Total* 57
80
33
5.71
2.95
11.43
*Average for 12 months.
tData unavailable.
*
*Total for 12 months.
-------
Thunderstorms occur on an average of about 20 days in a year. Heavy
rains are of short duration, but at times more than one inch of rain
falls during a heavy shower. Hail that accompanies a thunderstorm in
summer does little damage because the hailstones are generally small.
In the Area 15 valley the average daily range in temperature is great.
It averages nearly 30°F in December and January, and 43°F in summer.
The highest temperature observed during the period of record is 100°F
and the lowest is 9°F.
In the Area 15 valley the average growing season, or frost-free period,
extends from the middle of May to the middle of October, a period of
about five months. Frost has occurred, however, as late as June 1
and as early as September 20.
Table 1 gives the temperature and precipitation recorded at the WERL
dairy farm by the ESSA. The temperature has been recorded for 3^ years
and the precipitation for 8% years. These records correspond very
closely to the ones taken at Yucca Flat for the same period of time.
Vegetation.
The vegetation in Area 15 is typical of that found in semi-arid areas
of the Southwest. Generally, it consists of good growth of desert
shrubs and grasses.
The vegetation in Area 15 consists predominately of wolfberry
(Lycium andevsonii], small rabbitbrush (Chrysothamnus viscidifloras],
blackbrush (Coleogyne ramosissima], and Nevada joint-fir (Ephedra
nevadensis). Other common specTes that occur are winter fat (Eurotia
lanata], desert needlegrass (stipa speciosa], Indian ricegrass
(Orhyzopsis hymenoides}, Joshua tree (Yucca brevifolia], bud sage
(Artemisia spinescens ), squirrel tail (sitanion spp.), four-winged
saltbush (Atriplex canescens}, and a large number of species of
buckwheat.
A good stand of desert shrub and grass vegetative cover is present
•i
on the soils. The survey area of Area 15 normally has a plant
-------
density of 10 to 25 percent. The vegetative cover contributes
little organic matter to the soil, affords little protection
against erosion, and provides little shade for the soil. High
temperature, limited shade, and low organic matter content have
resulted in an adverse habitat for soil microorganisms; thus,
there is little microbial activity during much of the year.
'Chemical Analyses.
Since one of the primary purposes of this survey was to provide
data for use in the management of the WERL dairy farm, only
those soils which occur on the growing areas were analyzed
chemically.
Agricultural practices are considered to affect only the upper
6 to 10 inches of soil. The results presented in this report
are from the analysis of the surface samples from the agri-
cultural lands.
1. Standard Soils Analysis.
The methods used for the various analyses such as cation
exchange capacity, pH, exchangeable cations, conductivity,
total nitrogen and phosphate were taken from Jackson's
Soil Chemical Analysis(1).
2. Total Chemical Analysis.
The method used for the elemental analysis of the farm soils
is based on the preparation of standards by the addition of
appropriate reagent grade chemicals to a soil that has a
chemical matrix very similar to the average chemical matrix
of the farm soils.
These standards were prepared by adding the reagent grade
chemicals to five-gram samples of Carrizo soil (collected
in Arizona near Mesquite, Nevada). The samples were then
ground in a motorized mortar and pestle for fifteen minutes.
-------
Two grams of the ground soil aliquots were pelletized by the
method of Volborth(2). An examination of the data shows
obvious similarities and differences between the four soils.
For example, they are similar in cation exchange capacity,
exchangeable cations, conductivity, and pH. Hbwever, Thirsty
soil is much lower in carbonates than the other soils. (There
is also a very wide range in the molybdenum content of the
four soils.)
The samples of farm soil were ground and pelletized in the
same manner as the standards.
The samples were counted with a standard counter after every
eighth sample. The percent of the element of interest was
obtained by reading directly from the standard curve.
Although, not of a high degree of accuracy, this method ful-
fills the requirements for a study of this nature where the
variation between duplicate field soil samples frequently
has a range of ±10 percent of the mean. Comparisons between
analysis by the x-ray method agree well with the wet chemistry
methods.
3. Results.
The data are given in Appendix IX. The examination of the
data of Appendix IX shows similarities and differences among
the four soils. For example, they are similar in cation
exchange capacity, exchangeable cations, conductivity, and pH.
Thirsty soils have less than half the carbonates of the other
soils. They are similar in Ca, K, Cl, Mn, Fe, Al, Si02, Cu,
Zn, and N.
There is some variation in S, Ti, Mg, and phosphate. The widest
variation is the molybdenum content with a range of O.OC39 to
0.0112 percent.
Note.If further information is desired it can be found in the
Geologic Quadrangle - Geology of the Oak Spring Quadrangle - Nevada GQ214,
-------
III. SOIL MAPPING PROCEDURES
This soil survey was mapped according to the United States Depart-
ment of Agriculture 1960 Soil Classification System and the
7th Approximation System (see Appendix VI for map).
In general, this method involves digging soil pits or taking
soil auger borings to enable the surveyor to determine the strati-
graphy of the soil profile, the characteristics of the various layerss
and to make field measurements on certain chemical and physical
factors important to soil classification.
During the classification of the Area 15 soils eight pits were dug.
Using the information gained from these pits four soil series were
identified. The description of these series is presented below.
At the same time the soil profiles were described, samples of each
layer were taken for.physical and chemical analyses.
The four soil series described in this survey are:
1. Banded
2. Butte
3. Twin Peaks
4. Thirsty
Although these soils are given classification names, they should not
be considered as final, since this survey has not been correlated
with the U. S. National Cooperative Soil Survey.
The terminology of the descriptions is defined in the mapping legend
and in the Glossary which appear in Appendix VII and Appendix X,
respectively.
-------
1. Banded: The Banded series comprises Typic Durorthids, members
of sandy, mixed, calcareous, mesic family. Characteristically, the
soils have pale brown moderately alkaline A horizons of gravelly
sandy loam and very pale brown strongly alkaline C horizons grade
into silica Cca horizons that range from soft to very hard and have
a high content of silica and calcium carbonates (Cca).
Typifying Profile: Banded gravelly sandy loam (virgin)
(Color for dry conditions unless otherwise noted.)
Al 0 to 2 inches-Pale brown (10YR 6/3) gravelly sandy loam, dark
grayish brown (10YR 4/2) when moist; weak fine
platy structure; weak vesicular material between
pebbles; soft, very friable, nonsticky, nonplastic;
very few micro-roots, common fine interstitial
pores; violently effervescent; pH 8.4; abrupt
smooth boundary. (2 to 6 inches thick.)
Cl 2 to 12 inches-Very pale brown (10YR 7/3) gravelly sandy loam,
dark brown (10YR 4/3) when moist, weak fine sub-
angular blocky structure; soft, very friable,
nonsticky, nonplastic; few fine and micro-roots;
few fine interstitial pores; violently efferves-
cent; pH 8.8; clear smooth boundary. (8 to
18 inches thick.)
C2 12 to 24 inches-Very pale brown (10YR 7/3) very gravelly and cobbly
•sandy loam, dark brown (10YR 4/3) when moist; mas-
sive, soft friable, nonsticky, nonplastic; abundant
very fine, micro-roots, and few fine roots; few
fine interstitial pores; violently effervescent;
pH 9.0; abrupt wavy boundary. (8 to 20 inches
thick.)
-------
CSsica 24 to 40 inches-Very pale brown (10YR 7/3) very gravelly and
cobbly sandy loam with silica-lime, dark brown
(10YR 4/3) when moist; massive, soft, friable,
nonsticky, nonplastic; few micro-roots and fine
roots; violently effervescent; pH 9.0; clear
smooth boundary. (8 to 24 inches thick.)
C4sicam 40 inches+-White (10YR 8/2) silica-lime hardpan, very pale
brown (10YR 7/3) when moist; massive, very hard
firm, nonsticky, nonplastic; violently effer-
vescent; pH 9.2.
Type Location: 300 feet east and 1,000 feet south of the southwest
corner of WERL dairy farm in Area 15.
Range in Characteristics: Texture of the control section is coarse,
ranging from gravelly sandy loam to very gravelly, and cobbly sandy
loam modified by stones. The coarse fragment content varies from
10 to 30 percent with gravel usually predominating. Cobble content
is normally about 10 percent, but may vary from 5 to 20 percent. The
dry consistence of the silica Cca horizons range from soft to very
hard. The coarse fragments in the silica Cca horizons are always at
least lime coated on their undersides, but may have discontinuous
weakly lime-cemented bridging. Any profile will include a distinct
silica Cca horizon within 24 to 40 inches of the surface. This soil
has a silica lime hardpan at a depth between 36 and 48 inches.
Setting: Banded soils occur on nearly level to gently sloping
alluvial fans. The sediments are gravelly alluvium of coarse texture
that are high in tuff, rhyolite, granite and quartzite. The climate
is semi-arid with mean annual rainfall of 6 to 12 inches, hot dry
summers, and cool moist winters. Mean annual temperature is about
65°F, average January temperature about 40°F, and average July tempera-
ture about 80°F. The annual growing season is about 150 to 180 days.
10
-------
Drainage and Permeability: Excessively drained to the hardpan and very
slow through the pan. Runoff is very slow and permeability is rapid to
very rapid.
Use and Vegetation: This soil is being used as range with a low carrying
capacity. These soils support a good stand of blackbrush (Coleogyne
Tcmosissima], wolfberry (Lya-ium andersonii.), small rabbitbrush
(Chrysothamnus stenophyllus), winter fat (Eurotia lanata), Nevada joint-
fir (Ephedra nevadensis), Indian ricegrass (Orhyzopsis hymenoides],
Joshua tree (luoaa brevifolia), desert needlegrass (stipa speciosa),
and assorted annuals. The plant density is about 20 percent.
Distribution and Extent: Southern Nevada. This soil occurs on a small
area of the survey.
Series Proposed: Nevada Test Site, Area 15, Nye County, Nevada, 1966.
Banded is the name of a mountain near the WERL dairy farm on NTS.
11
-------
2. Butte: The Butte series comprises Typic Torrifluvents, member of
a coarse sandy, mixed, calcareous, mesic family. Characteristically,
the soils have dark brown moderately alkaline A horizons of sandy loam
and brown or yellowish brown moderately alkaline C horizons of gravelly
sandy loam grading with depth into sandy, gravelly, and cobbly alluvium.
Typifying Profile: Butte loamy sandy irrigated pasture.
(Colors for dry conditions unless otherwise noted.)
Al 0 to 4 inches-Pale brown (10YR 6/3) sandy loam, dark brown
(10YR 4/3) whe.n moist; weak medium subangular
blocky strucutre; soft, friable, nonsticky, non-
plastic; very few micro-roots; common fine
interstitial pores; violently effervescent;
pH 8.4; abrupt smooth boundary. (3 to 8 inches
thick.)
Cl 4 to 10 inches-Very pale brown (10YR 7/3) loamy sand, yellowish
brown (10YR 5/4) when moist; weak fine sub-
angular blocky structure; soft, friable, non-
sticky, nonplastic; few fine, medium, and micro-
roots; common fine interstitial pores; violently
effervescent; pH 8.4; clear smooth boundary.
(4 to 12 inches thick.)
C2 10 to 16 inches-Light yellowish brown (10YR 6/4) gravelly loamy
sand, yellowish brown (10YR 5/4) when moist;
weak fine subangular blocky structure; soft,
friable, nonsticky, nonplastic; plentiful micro-
roots and few fine roots; common fine interstitial
pores; violently effervescent; pH 8.6; clear smooth
boundary. (4 to 12 inches thick.)
C3 16 to 29 inches-Very pale brown (10YR 7/3) gravelly loamy sand,
brown (10YR 5/3) when moist, weak fine subangular
blocky breaking to single grain; loose, nonstickys
12
-------
nonplastic, plentiful very fine, micro-roots and
few fine roots; few interstitial pores; violently
effervescent; pH 8.8; clear smooth boundary,
(8 to 20 inches thick.)
C4 29 to 39 inches-Pale brown (10YR 6/3) gravelly loamy sand,
brown (10YR 5/3) when moist, massive; loose,
nonsticky, nonplastic, few fine and micro-
roots and few fine interstitial pores; violently
effervescent; pH 8.8; clear smooth boundary.
(8 to 18 inches thick.)
C5 39 to 60 inches+-Light yellowish brown (10YR 6/4) gravelly loamy
sand, dark brown (10YR 4/3) when moist; massive
soft, friable, nonsticky, nonplastic; few fine
and micro-roots; violently effervescent; pH 8.8.
Type Location: Southeast corner of WERL dairy farm in Area 15.
Range in Characteristics: Texture of the control section is moderately
coarse to coarse, ranging from fine sandy loam to sand and modified by
gravel, cobbles, or stones. The coarse fragment content varies from
10 to 30 percent with gravel usually predominating. Cobble content is
normally about 10 percent, .but may vary from ,5 to 20 percent. Stones
usually will not exceed 5 percent except on the ridges in the area.
The C horizon may have a silica-lime cementation.
Setting: Butte soils occur in nearly level to gently sloping alluvial
fans. The sediments are gravelly alluvium of coarse texture that are
high in tuff, rhyolite, granite, and some quartzite that have come
mainly from igneous and metasedimentary rocks. The climate is semi-
arid with mean annual rainfall of 6 to 12 inches, hot dry summers, and
cool moist winters. Mean annual temperature is about 65°F, average
January temperature about 40°F, and average July temperature about
80°F. The annual growing season is between 150 to 180 days.
13
-------
Drainage and Permeability: Well drained, with slow runoff and moder-
ately rapid to rapid permeability. Infiltration may be moderate to
rapid in cultivated areas.
Native Vegetation: Wolfberry (lyoium andersonii ), small rabbitbrush
(Chrysothamnus stenophyIlus), Indian ricegrass (Orhyzopsis hymenoides),
four-winged saltbush (Atriplex oanescens), Joshua tree (Yucca brevifolia)
winter fat (Eurotia lanata], desert needlegrass (stipa speoiosa], and
assorted annuals. The plant density is about 20 percent, except in years
having good rainfall when annuals predominate the site.
Use: Much of this soil is used on range with a low carrying capacity.
Some of it is being used for cultivated crops such as alfalfa, barley,
oats, and sudan grass by WERL.
Distribution and Extent: Southern Nevada and probably in parts of
southeastern California, western Arizona, and southwestern Utah.
Series Proposed: Nevada Test Site, Area 15, Nye County, Nevada.
Butte is the name of a hill on the Eleana Range inside NTS (Big Butte).
14
-------
3. Twin Peaks: The Twin Peaks series comprises Typic Tom'fluvents,
member of coarse loamy, mixed, calcareous, mesic family. Characteris-
tically the soils have pale brown moderately alkaline A horizons of
fine sandy loam and very pale brown strongly alkaline C horizons of
fine sandy loam grading to gravelly loamy sand. This soil also has
a buried B2 horizon that is light reddish brown with common fine
distinct pinkish white silica-lime streaks and a texture of sandy
loam. The B2b horizon is moderately alkaline.
Typifying Profile: Twin Peaks fine sandy loam.
(Colors for dry conditions unless otherwise noted.)
Al 0 to 5 inches-Pale brown (10YR 6/3) fine sandy loam, dark brown
(10YR 4/3) when moist; weak medium subangular
blocky structure; soft, friable, nonsticky, non-
plastic; plentiful micro-roots and few fine roots;
many fine interstitial pores; violently efferves-
cent; pH 8.4; abrupt smooth boundary. (3 to
12 inches thick.)
Cl 5 to 16 inches-Very pale brown (10YR 7/3) fine sandy loam, dark
brown (10YR 4/3) when moist; weak medium sub-
angular blocky structure; soft, friable, nonsticky,
nonplastic; plentiful micro-roots and few fine
roots; many fine interstitial pores; violently
effervescent; pH 8.6; clear smooth boundary.
(8 to 20 inches thick.)
C2 16 to 28 inches-Pale brown (10YR 6/3) gravelly sandy loam brown
(10YR 5/3) when moist; massive, soft very friable,
nonsticky, nonplastic; few fine roots; common fine
interstitial pores; violently effervescent, pH 8.6;
clear smooth boundary. (8 to 24 inches thick.)
15
-------
B2b 28 to 48 inchest-Light reddish brown (SYR 6/4) sandy loam with
common fine distinct pinkish white (5YR 8/2)
silica-lime streaks, reddish brown (SYR 5/4)
when moist; strong medium subangular bloeky
structure; hard, friable, slightly sticky,
nonplas-tic; very few micro-roots; many medium
and fine tubular pores; common thin clay
films on peds and in pores; strongly effer-
vescent; pH 8.4.
Type Location: About 300 feet south and 600 feet east of the north-
east corner of WERL dairy farm in Area 15.
Range in Characteristics: Texture of the control section is moderately
coarse to coarse, ranging from sandy loam to gravelly loamy sand. The
buried B horizon may be found between 20 and 56 inches of the surface
and may have a silica-lime cementation in the lower horizons.
Setting: Twin Peaks soils occur in nearly level to gently sloping
alluvial fans. The sediments are sandy alluvium of moderately coarse
texture that are high in tuff, rhyolite, granite and some quartzite
that have come mainly from igneous and sedimentary rocks.
The climate is semi-arid with mean annual rainfall of 6 to 12 inches,
hot dry summers, and cool moist winters. Mean annual temperature is
about 65°F, average January temperature about 40°FS and average July
temperature 80°F; the annual growing season is between 150 and 180 days.
Drainage and Permeability: Well drained, with slow runoff and mod-
erately rapid permeability. Infiltration may be moderate to moderately
rapid if cultivated.
Native Vegetation: Wolfberry (Lycium andersonii], blackbrush (Coleogyne
ramosissima), small rabbitbrush (Chrysothamnus stenophyllus), Nevada
joint-fir (Ephedra nevadensis), winter fat (Eurotia lanata), desert
needlegrass (stipa spedosa], Joshua tree (yucca brevifolia), Indian
ricegrass (Orhyzopsis hymenoides), bud sagebrush (Artemisia spinesaens),
16
-------
and squirrel tail (s-itanion spp,). The plant density is about
20 percent, except in years having good rainfall when annuals
predominate the site.
Use: All of this soil is used as range with a low carrying capacity.
This soil would be well adapted for cultivated crops,
Distribution: Southern Nevada.
Series Proposed: Twin Peaks is the name of a mountain located
inside NTS, Area 15, Nye County, Nevada.
17
-------
4. Thirsty: The Thirsty series comprises Typic Torrifluvents member
of sandy skeletal, mixed, calcareous, mesic family. Characteris-
tically the soils have dark brown moderately alkaline A horizons of
sandy loam and brown, or yellowish brown, moderately alkaline C hori-
zons of gravelly sandy loam grading with depth into sandy, gravelly
and cobbly alluvium.
Typifying Profile: Thirsty cobbly sandy loam, irrigated pasture.
(Colors for dry conditions unless otherwise noted.)
Al 0 to 5 inches-Pale brown (10YR 6/3) cobbly sandy loam, dark
brown (10YR 4/3) moist; weak medium subangular
blocky structure; soft, very friable; nonsticky,
nonplastic; plentiful fine and medium roots,
common fine interstitial pores; strongly effer-
vescent; pH 8.4; abrupt smooth boundary.
(3 to 8 inches thick.)
Cl 5 to 13 inches-Pale brown (10YR 6/3) cobbly sandy loam, dark
brown (10YR 4/3) moist; weak fine subangular
blocky; structure, soft; very friable; non-
sticky, nonplastic; abundant micro-roots and
plentiful fine roots; common fine interstitial
pores; strongly effervescent, pH 8,4; clear-
smooth boundary. (5 to 12 inches thick.)
C2 13 to 26 inches-Very pale brown (10YR 7/3) cobbly and gravelly
loamy sand, brown (10YR 5/3) moist; massive;
soft; loose; nonsticky, nonplastic; plentiful
fine, medium, and micro-roots; strongly
effervescent, pH 8.6; clear smooth boundary.
(10 to 20 inches thick.)
18
-------
C3 26 to 60 inchest-Very pale brown (10YR 7/3) very gravelly loamy
sand, brown (10YR 5/3) moist; massive; loose;
nonsticky, nonplastic; few micro-roots and
i
very few fine roots; slightly effervescent,
pH 8.6.
Type Location: Nye County, Nevada; approximately center of
WERL dairy farm in Area 15.
Range in Characteristics: Texture of the control section is moderately
coarse to coarse, ranging from fine sandy loam to sand and modified
by gravel, cobbles, or stones. The coarse fragment content varies
from 20 to 50 percent with gravel usually predominating. Cobble con-
tent is normally about 20 percent but may vary from 5 to 30 percent.
Stones usually will not exceed 5 percent except on the ridge running
through the area, where they may be as high as 30 percent.
Setting: Thirsty soils occur in nearly level to gently sloping
alluvial fans. The sediments are gravelly alluvium of coarse
texture that are high in tuff, rhyolite, granite and some quartzite
that have come mainly from igneous and metasedimentary rocks. The
climate is semi-arid with mean annual rainfall of 6 to 12 inches,
hot dry summers, and cool moist winters. Mean annual temperature
is about 65°F, average January temperature is about 40°F, and average
July temperature about 80°F. The annual growing season is between
150 to 180 days.
Drainage and Permeability; Well to excessively drained with slow runoff
and moderately rapid to apid permeability. Infiltration may be
moderately rapid to rapid in cultivated areas.
Native Vegetation: Blackbrush (Coleogyne romosissima], wolfberry
(Lyoium andevsonii}, small rabbitbrush (Chrysothamnus stenophyllus),
Nevada joint-fir (Ephedra nevadensis), four-winged saltbush
(Atriplex oanescens], bud sagebrush (Artemisia spinescens), Joshua
tree (luoaa brevifolia), winter fat (Eurotia lanata), Indian ricegrass
(Orhyzopsis hymenoides), and desert needlegrass (stipa speoiosa].
19
-------
Use: Much of this soil is used as range with a very low carrying
capacity. Some of this soil is being used for cultivated crops
such as alfalfa, barley, oats, and sudan grass. Native plant density
is about 15 percent, except in years having good spring rains when
annuals predominate the site.
Distribution and Extent: Southern Nevada and probably in parts of
southeastern California, western Arizona, and southwestern Utah.
Series Proposed: Nevada Test Site, Area 15 on WERL dairy farm,
Nye County Nevada, 1966. Thirsty is a name of a canyon near
NTS.
20
-------
BIBLIOGRAPHY
1. Jackson, M. L., Soil Chemical Analysis. Prentice-Hall, Inc.
Englewood Cliffs, New Jersey. 1960. 498 pp.
2. Volborth, A., Total Instrumental Analysis of Rocks. Nevada
Bureau of Mines, Report No. 6. 1963.
3. Munsell Color Company, Inc., Baltimore, Maryland.
21
-------
Appendix I. Classification and Characteristics of Soil
ro
Series
Banded
Butte
Twin Peaks
Thirsty
Texture
Coarse
gravelly
Coarse
Moderate
coarse
Moderately
coarse
gravel ly
cobbly
Permeability
Rapid to
very rapid
Rapid to
very rapid
Moderate
rapid
Moderate
rapid to
rapid
nm'mnp °' fiTo Surface Soil Parant Material
ZONAL
Excessive High 10YR 6/3 10YR 4/2 Gravelly alluvium
from a wide variety
of igneous and
sedimentary rock.
AZOMAL
Well to Mod- 10YR 6/3 10YR 4/3 Mixed but dorrrinantly
excessive erate tuff, rhyolite,
granite and quartzite
Well Mod- 10YR 6/3 10YR 4/3 Mixed but dominantly
erate - tuff, rhyolite,
granite and quartzite
Well to Mod- 10YR 6/3 10YR 4/3 Mixed but dominantly
execssive erate tuff, rhyolite,
granite and quartzite
-------
Appendix II. Soil Symbols With Descriptions Describing Each Digit.
SYMBOLS:
1S57*
*1 = Depth of soil (over 60")
S = Texture of soil
5 = Permeability of surface soil
7 = Permeability of substratum
tA = Slope (which is none to slight)
1 = Erosion (which is slight)
1S53 Very deep fine sandy loam over sandy loam, nearly level to
A-2 slightly sloping with moderate erosion.
1S57 Very deep sandy loam over coarse sands, gravel, and some cobbles,
A-l nearly level to slightly sloping, with slight erosion.
lgS6 Very deep gravelly sandy loam throughout with few cobbles, nearly
A~^llevel to slightly sloping, with slight erosion.
lgS57 Very deep gravelly sandy loam underlain with coarse sand and
A~-lcobbles, nearly level to slightly sloping with slight erosion.
lvgS7 Very deep very gravelly sandy loam over coarse sands and cobbles,
B-2 gently sloping with moderate erosion.
lkS57 Very deep cobbly and gravelly sandy loam over coarse sands and
B-2 gravel', gently sloping with moderate erosion.
3gS5R Moderately deep gravelly sandy loam over cemented hardpan (caliche)
A-2 nearly level to slightly sloping with moderate erosion.
4gS5R Shallow gravelly sandy loam over cemented silica hardpan (caliche)
A-2 nearly level to slightly sloping with moderate erosion.
4kS5R Shallow cobbly and gravelly sandy loam over cemented silica hard-
B-2 pan (caliche) gently sloping with moderate erosion.
23
-------
Appendix III. Soil Capability Units,
1. IIS4 Very deep (over 36") moderately coarse textured soils, with
sand substrata or gravelly loamy sand and gravelly sandy
loam substratum; moderate available water holding capacity
(1.0 to 1.5"/ft); nearly level slopes; well drained, slight
erosion.
2. IVS4 Very deep (over 36") gravelly moderately coarse textured
soils; well drained; low available water holding capacity
(.75 to l"ft) nearly level, slight erosion.
3. VIIS4 Moderately deep (20 to 36") gravelly and very gravelly
moderately coarse and coarse textured soils; well to
excessively drained; low to very low available water
holding capacity; nearly level to gently sloping,
moderate erosion.
4. VIIS7 Very deep (over 36") stony and cobbly moderately coarse
textured soils; well drained; low available water holding
capacity; gently sloping, moderate erosion.
5. VIIS8 Moderately deep to shallow (10 to 36") gravelly and very
gravelly moderately coarse textured soils; over silica
lime hardpan; very low to low available water holding capa-
city (.75 to I"/ft) well drained, nearly level, moderate
erosion.
6. VIIcK Very deep (over 60") moderately coarse textured soils;
well drained;high available water holding capacity;
nearly level slopes. Irrigation water not available;
moderate erosion.
24
-------
Appendix IV. Soil Classification.
Soil
Series
1938
Yearbook
7tn /Approximation
Subgroup Family
Banded
Calcisol Typic Durorthids
Sandy, mixed, calcareous,
mesic.
Butte
Alluvial Typic Torrifluvents
Coarse sandy, mixed,
calcareous, mesic.
Twin Peaks Alluvial Typic Torrifluvents
Coarse loamy mixed
calcareous, mesic.
Thirsty
Alluvial Typic Torrifluvents Sandy skeletal, mixed
calcareous, mesic.
25
-------
APPENDIX V- CONVENTIONAL MAPPING SYMBOLS FOR
SOIL SURVEY FIELD SHEET
MAPPING SYMBOLS FOR SURVEY FIELD SHEET
Hard Surfaced Roads E^r KlZJl^^Fg^f $,;£3TK;w;i E,sa gr-ai
Good Gravel Road ZIIZZZZZZZZZZZIZZZZZZZZZZZZZZZZZ
Poor Dirt Road • ZZZZZZZZZZZZZZZZ
Pipe Line (Water) -H I 1 I * «—-» • 1 I i I 1 I
Power-transmission Line ©—~©——© © ©——© ©——
Wells O Wel1
Intermittent Streams
Soil Survey Area Boundary
Soil Boundary
26
-------
Appendix VI. Aerial Map - Area 15 WERL Dairy Farm
-------
APPENDIX VII. SOIL SURVEY MAPPING LEGEND
This legend lists and defines the mapping symbols for soil, slope,
erosion, and other physical land factors which will be used for soil
surveys on the range area of NTS.
Order of Symbols
The land mapping symbol shows soil characteristics, slope erosion, and
additional land factors of wetness, salinity, and overflow if signifi-
cant. Symbols are written in fractional form with soil characteristics
in the numerator and slope, erosion, and additional land factors in the
denominator. Soil series will be shown by attaching an identifying
symbol to the numerator of the fractional symbol.
Delineations
Soil Type and Phase Boundary: Solid black lines.
Land Use Boundary: Dashed lines (1/8")
Symbols for Soil Characteristics
Order of symbols to show soil characteristics is as follows: First,
the effective depth, then, the texture; then, the permeability of
the upper subsoil; then the permeability of the lower subsoil; finally,
the type of underlying material if significant.
Type of underlying material will be shown whenever it limits the effec-
tive depth. The permeability of the lower subsoil will be omitted when
this is not significantly different from that of the upper subsoil.
Permeability of lower subsoil is also omitted when depth symbol is 4.
Permeability of both upper and lower subsoil is omitted when depth
symbol is 5.
28
-------
EFFECTIVE DEPTH
Symbol:
1
2
3
4
5
Over 60 inches
36 - 60 inches
24 - 36 inches
12 - 24 inches
Less than 12 inches
Descriptive Term
Very deep
Deep
Moderately deep
Shallow
Very shallow
TEXTURE
Symbol
H
F
M
S
L
C
X
Descriptive Term
Heavy
Moderately heavy
Medium
Moderately coarse
Coarse
Very coarse
Undifferentiated
Included Texture Classes
Clay, silty clay
Sandy clay, silty
clay loam
Silt loam, loam,
very fine sandy
loam
Fine sandy loam,
sandy loam
Loamy fine sand,
loamy very fine
sand,loamy sand
Fine sand, sand,
and coarse sand
MODIFIERS OF TEXTURE (Placed before-texture symbol)
Symbol Descriptive Term
g Gravelly
r Very gravelly
s Stony or cobbly
Limiting crop adapta-
tion and moisture-
holding capacity
Enough gravel to pre-
vent cultivation
Enough stone to
hinder cultivation
29
-------
PERMEABILITY
Symbol
2
3
4
5
6
7
Class
Slow
Moderately slow
Moderate
Moderately rapid
Rapid
Very rapid
Approximate Rate
(Inches Per Hour)
.05 - 2.0
.20 - .80
.80 - 2.50
2.50 - 5.00
5.00 -30.00
More than 10.00
TYPE of LIMITING or UNDERLYING MATERIAL
Symbol
V
R
Y
Z
Type of Material
Lacustrine sediments
Lime or lime-silica hardpan
Dense very slowly permeable clay
Gravel
Probable
Texture
H or F
F or M
M or S
S
L
C
One set of slope classes will be mapped. In symbolizing slope, slope
class letters only will be placed in the fractional symbol. For
hummocky micro-topography a double slope class letter will be used.
Slope Class
Symbol
A
B
AB
C
BC
DE
EF
AA
BB
^Percent of slope
Range
0 - 2 *
2-4
0-4
4 - 8
2 - 8
8 - 30
15 - 45+
0 - 2
2-4
Des c rip_tj ve Te_rrn
Nearly level
Gently sloping
Nearly level to gently sloping
Moderately sloping
Gently to moderately sloping
Strongly sloping to steep
Steep to very steeply sloping
Nearly level with hummocks
Gently sloping with hummocks
30
-------
Erosion
Symbol
1
2
4
N
Descriptive lerm
i^o apparent or slight erosion
Moderate erosion
Very severe erosion
Very severe wind erosion (large dunes)
Degree of Wetness
Symbol
Wl
W2
W3
Descriptive Term and Range
Moderately wel1 drained: Profile is wet for a small but
significant part of the time, usually because of a slowly
permeable layer within or immediately beneath the solum,
a relatively high or intermittently high water table
(usually below 5 feet), surface additions of water by
runoff from areas higher up the slopes, or a combina-
tion of those conditions. (This class is particularly
difficult to assess in drier climates or where winter
rainfall occurs when temperatures are low enough to almost
inhibit growth.) Evidence includes somewhat thicker and
darker A horizons as contrasted to those of well drained
soils (grass vegetation), mottling in the lower B horizons
or within 36 to 60 inches of the surface or both.
Imperfectly^ or somewhat poorly drained: Soil is wet for
significant periods, but not all of the time, usually
because of a slowly permeable layer or a high water
table. Field evidences of imperfect drainage are the
presence of a water table (at depths of 36 to 60 inches),
distinct gleying within 18 to 36 inches of the surface
ususually thick and dark A horizons (related to abundant
growth of coarser grasses and slower decomposition rates
because of wetness), pronouced accumulations of water
soluble salts within 36 inches, or a combination of these.
Arti icial drainage is needed for the growth of most deep
rooted crops and many others that are sensitive to poor
aeration. Orainaqe may also be necessary to maintain a
favorable salt balance.
Poorly drained: The soil remains wet much of the time with
TRe water tab1e seasonally near the surface for prolonged
intervals. Field evidences of poor drainage are the
presence of a high water table (at depths of 18 to 36 inches),
gleying near the surface (above 18 inches), and pronouced
31
-------
Symbol Descriptive Ter^i and Range (Continued!
W3 accumulations of water soluble salts at or near the surface
in saline areas. Soils usually lack peaty or mucky surface
horizons. Drainage is necessary for the growth of important
crops. Grazing is possible most of the time, and hay can
usaully be harvested,
W4 Very poorly drained: The water table remains at or near the
surface a greater part of the time. Field evidences of very
poor drainage are the presence of a very high water table
(at depths above 18 inches), a peaty or mucky surface
horizon, and gleying at or near the surface (i.e. hues
yellower than 10YR and/or chromas of /2 or less and/or
distinct discontinuous phase of the pattern). Soils that
are very poorly drained due to a moving water table may
have oxidized rather than reduced colors because of dis-
solved oxygen in the water. Drainage is a minimum pre-
requisite for the growth of important crops. Usually graz-
ing is possible, at least seasonally, and hay may be harvested
in drier years.
Sali ni ty
Symbol
Ho symbol
SI
S2
S3
Range
(% Salt)
Less than 0.15
0.15 - 0.35
0.35 - 0.65
Range-Conductivity
Saturation Extract
(Ec 10' A 25°C)
Less than 4
4 - 3
8 - 15
0.65 - or greater 15 or greater
Descriptive Term
Free
Slight
Moderate
Severe
Alkalinity
Symbol
[Jo symbol
al
a2
Descriptive Term
Free
Slight to moderate
Severe
32
-------
Overflow
Symbol Descriptive Term
fl Occasional overflow
33
-------
Appendix VIII. Physical Analysis of Soils.
Soil
Hori-
zon
Depth Textural Class
Gravel
Particle-size Distribution
Very coarse
sand (2.0
- 1.0 mm)
Coarse sand Medium nne Very Fine Silt Clay<
(1.0 - 0.5 sand (0.5- sand (0.25 sand(0.10- (0.05 (0.002
mm) 0.25 mm) -0.10 mm} 0.05 mm) -0.002 mm) mm)
Banded, gravelly
sandy loam
Location: Area 15
Farm, NTS
Survey Hole No. 8
Butte, loamy
Sand
Location: Area 15
Farm NTS
Survey Hole No. 1
Twin Peaks, fine
sandy loam
Location: Area 15
Farm, NTS
Survey Hole No. 6
AI
Ci
C2
C3sica
C^s i cam
A!
Ci
C2
C3
C,
Cs
AI
Ci
C2
B2b
0-2"
2-12"
gravelly sandy loam
gravelly sandy loam
12-24" very gravelly and cobbly sandy loam
24-40"
40"+
0-4"
4-10"
10-16"
16-29'!
29.39..
39-60"
0-5"
5-16"
16-28"
28-48"
very gravelly and cobbly sandy loam
silica-lime hardpan
Loamy sand
Loamy sand
gravelly loamy sand
gravelly loamy sand
gravelly loamy sand
gravelly loamy sand
fine sandy loam
fine sandy loam
sandy loam
+sandy loam
25
23
25
61
12
15
22
23
32
32
9
11
23
18
11
12
13
14
12
26
11
10
13
11
15
15
14
25
34
23
18
17
17
24
15
12
13
15
13
18
19
22
13
20
25
23
21
20
23
23
24
16
15
19
20
15
4
19
15
22
20
14
11
22
21
14
12
20
18
19
8
12
12
22
21
21
20
10
10
10
10
15
14
18
21
14
27
6
7
1Z
13
11
"10
14
-------
Appendix VIII. Physical Analysis of Soils. (Continued)
Gravel Particle-size Distribution
„ . A'ery coarse
Soil Depth Textural Class sand (2.0
- 1 .0 mm)
Coarse sand
(1.0 - 0.5 -
mm)
Medium
Sand(0.5 -
0.25 mm)
Fine
Sand(0.25
-0.10 mm)
Very fine
sand(0.10-
0.05 mm)
Silt
(0.05
-0.002 mm)
Clay<
(0.002
mm)
Thirsty, Cobbly Aj 0-5"
sandy loam Cj 5-13"
Location: Area 15 C2 13-26"
Farm, NTS C3 26-60"+
Survey Hole No. 5
cobbly sandy loam 15 7
cobbly sandy loam 19 9
cobbly and gravelly loamy sand 40 12
very gravelly loamy sand 31 11
15
17
22
23
20
21
23
24
20
21
20
21
22
16
8
7
11
11
10
9
-------
APPENDIX IX, ANALYSIS OF FARM SOILS
Soil Code
Name
Soil Survey Code
Capability Unit
Cation Exchange Cap.
(meq/100 g)
Exchangeable Cations
(meq/100 g)
Ca
Mg
Na
K
Conductivity
(mmhos)
pH
Carbonates % as
CaCO-j equivalents
K
Ca
Na
S
Ti
Cl
Mn
Fe
Al
Si09
Cu
-------
APPENDIX X. GLOSSARY
ABC soil. A. soil that has a complete profile, including an A, B, and
C horizon.
AC soil. A soil that has an A and C horizon but no B horizon. Commonly
such soils are immature, as those developing from alluvium or those
on steep, rocky slopes.
Aeration, soil. The exchange of air in soil with air from the atmosphere.
The air in a well-aerated soil is similar to that in the atmosphere;
but, that in a poorly aerated soil is considerably higher in carbon
dioxide and lower in oxygen.
Alluvial fan. A fan-shaped deposit of sand, gravel, and fine material
dropped by a stream where its gradient lessens abruptly.
Alluvium. Fine material, such as sand, silt, or clay, that has been
deposited on land by streams.
Aspect (forestry). The direction toward which a slope faces. Synonym:
Exposure.
Available moisture capacity. The difference between the amount of water
in a soil at field capacity and the amount in the same soil at the
permanent wilting point. Commonly expressed as inches of water per
inch depth of soil.
Badlands. Areas of rough, irregular, denuded land in which most of the
surface is occupied by ridges, gullies, and deep channels.
Bedrock. The solid rock that underlies the soil and other unconsolidated
material or that is exposed at the surface.
Buried soil. A developed soil, once exposed but now overlain by more
recently formed soil.
Calcareous soil. A soil containing enough calcium carbonate (often
with magnesium carbonete) to effervesce (fizz) visibly when
treated with cold dilute hydrochloric acid.
Caliche. A more or less cemented deposit of calcium carbonate in many
soils of warm-temperature areas, as in the southwestern states.
The material may consist of soft, thin layers in the soil or of
hard, thick beds just beneath the sol urn or it may be exposed at
the surface by erosion.
Clay. As a soil separate, the mineral soil particles less than 0.002
millimeter in diameter. As a soil textural class, soil material
that is 40 percent or more clay, less than 45 percent sand, and
less than 40 percent silt.
37
-------
Clay film. A thin coating of clay on the surface of a soil aggregate.
Synonyms: Clay coat, clay skin.
Claypan, A compact, slowly permeable soil horizon that contains more
clay than the horizon above and below it. A claypan is commonly
hard when dry and plastic or stiff when wet.
Coarse fragments. Minerals or rock particles more than 2 millimeters
in diameter.
Coarse-textured soil. Sand and loamy sand.
Complex, soil. A mapping unit consisting of different kinds of soils
that occur in such small individual areas or in such an intricate
pattern that they cannot be shown separately on a publishable soil
map.
Consistence, soil. The feel of the soil and the ease with which a
lump can be crushed by .the fingers. Terms commonly used to
describe consistence are--
Loose. Noncoherent; will not hold together in a mass.
Friable. When rnoist, crushed easily under gentle to moderate
pressure between thumb and forefinger and can be pressed
together into a lump.
Fi rm. When moist, crushed under moderate pressure between
thumb and forefinger, but resistance is distinctly noticeable.
Plastic^ When wet, readily deformed by moderate pressure but
can be~pressed into a lump; will form a wire when rolled
between the thumb and forefinger.
Sticky. When wet, adheres to other material; tends to stretch
somewhat and pull apart, rather than pull free from other material.
Hard. When dry, moderately resistant to pressure; can be broken
with difficulty between thumb and forefinger.
Cemented. Hard and brittle; little affected by moistening.
Continental climate. The climate in areas distant from the ocean;
characterized by considerable variation in temperature and in
other weather conditions.
Contour. An imaginary line connecting points of equal elevation on
the surface of the soil.
Dolomite. Rock consisting mainly of magnesium carbonate and calcium
carbonate; limestone or marble with much magnesium carbonate in it.
Dune. A mound or ridge of loose sand piled up by the wind.
Duripan. Subsurface horizon that is cemented by silica, usually opal
or macrocrystalline form of silica, to the point that fragments
from the air-dry horizon will not slake in water or acid.
Erosion. The wearing away of land surface by wind, running water, and
other geological agents.
Erosion pavement (geology). A layer of coarse fragments of gravel or
stones on the surface of the ground, which remains after the fine
particles are removed by erosion.
38
-------
Fine-textured soils. Moderately fine textured: Clay loam, sandy clay
loam, silty clay loam; fine-textured; sandy clay, silty clay, and
clay. Roughly, soil that contains 35 percent or more of clay.
Flood plain. Nearly level land, consisting of stream sediment, that
borders a stream and is subject to flooding unless protected
artificially.
Fluvial. Flood plains.
Forage. Plant material that can be used as feed by domestic animals;
it may be grazed or cut for hay.
Genesis, soil. The manner in which the soil originated, with special
reference to the processes responsible for the development of
the solum, or true soil, from the unconsolidated parent material.
Granite. A very hard, igneous rock, usually gray or*pink, consisting
chiefly of crystalline quartz, feldsparf and mica.
Gravelly soil material. From 15 to 50 percent of material by volume,
consists of rounded or angular rock fragments that are not
prominently flattened and are up to 3 inches in diameter.
Grazing capacity. The maximum number of animals or animal units per
acre, or acres per animal unit, that a grazing area can support
adequately without deterioration; sometimes called carrying capacity.
Gully. A miniature valley with steep sides cut by running water through
which water ordinarily runs only after rains. The distinction bet-
ween gully and rill is one of depth. A gully generally is an
obstacle to farm machinery and is too deep to be obliterated by
normal tillage, whereas, a ri11 is of lesser depth and can be
smoothed over by ordinary tillage.
llardpan. A hardened or cemented soil horizon, or layer. The soil
material may be sandy or clayey, and it may be cemented by iron
oxide, silica, calcium carbonate, or other substances.
Horizon, soil. A layer of soil, approximately parallel to the surface,
that has distinct characteristics produced by soil-forming pro-
cesses. The relative position of the several soil horizons in a
typical soil profile, and their nomenclature, are as follows:
A« Organic debris, partly decomposed or matted.
A, A dark-colored horizon having a fairly high content of organic
matter mixed with mineral matter.
!\2 A light-colored horizon, often representing the zone of maximum
leaching where podzolized; absent in wet, dark-colored soil.
A, Transitional to B horizon but more like A than B; sometimes
absent.
B, Transitional to B horizon but more like B than A; sometimes
absent.
B~ A usually darker colored horizon, which often represents the
zone of maximum illuviation where podzolized.
B^ Transitional to C horizon.
39
-------
The ,"' horizons make up a zone of eluviation, or leached zones. The
B horizons make up a zone of ill aviation, in which clay and other
materials have accumulated. The A and B horizons, taken together,
are called the sol urn, or true soil.
Hue. One of the three variables of color. The dominant spectral (rain-
bow) color; it is related to the dominant wavelength of the light.
See Munsell notation.
Igneous rock. Rock that has been formed by the cooling of molten
mineral material. Example: Granite, syenite, diorite, and gabbro.
Illuviation. The accumulation of material in a soil horizon through the
deposition of suspended material and organic matter removed from
horizons above. Since part of the fine clay in B horizon (or sub-
soil) of many soils has moved into the B horizon from the A horizon
above, the B horizon is called an illuvial horizon.
Indicator plants (ecology). Plants that give reliable information con-
cerning present condition and past history of an area as to soil,
alkalinity, salinity, climate, depth to water table, overgrazing,
fire, and the use to which the area is best adapted.
Inherited soil characteristic. Any characteristic of a soil that re-
sults directly from the nature of the material from which it was
formed, as contrasted to characteristics that are wholly or partly
the result of soil-forming processes acting on parent material. For
example, some soils are red because the parent material was red, but
the color of most r<5d soils is the result of the soil-forming pro-
cesses.
Lacustrine deposit (geology). Material deposited in lake water and
exposed by lowering of the water level of elevation of the land.
Land. The total natural and cultural environment within which produc-
tion taken place. Land is a broader term than soil. In addition
to soil, it applies to mineral deposits and water supply; location
in relation to centers of commerce and population; the size of the
individual tracts or holdings; and the existing plant cover works
of improvement, and the like.
Land classification. The classification of units of land for the purpose
of showing their relative suitabilities for some specific use.
Leached layer. A layer from which the soluble materials have been dis-
solved and washed away by percolating water.
Lime. Chemically, lime is calcium oxide (CaO), but its meaning has been
extended to include all limestone-derived materials applied to
neutralize acid soils. Agricultural lime can be obtained as ground
limestone, hydrated lime, or burned lime, with or without magnesium
minerals. Basic slag, oystershe ils, and marl also contain calcium.
Lime concretion. An aggregate cemented by the precipitation of calcium
carbonate (CaC00).
40
-------
Mechanical analysis (soils). The percentage of the various sizes of
individual mineral particles, or separates in the soil. Also
a laboratory method of determining soil texture.
Medium-textured soil. Soil of very fine sandy loam, loam, silt loam,
or silt texture.
Mesic. Temperature range-less than near annual 59°F greater than the
mean annual 47°F medium temperature between hot desert and cold
uplands.
Mica. Primary alumino-silicate minerals in which two silica layers
alternate with one alumina layer. The layers separate readily into
thin sheets or flakes.
Micro-organisms. Forms of life that are either too small to be seen
with the unaided eye or are barely discernible.
Montmorillonite. A fine, platy, alumino-silicate clay mineral that
expands and contracts with the absorption and loss of water. It
has a high cation-exchange capacity and is plastic and sticky
when moist.
Morphology, soil. The makeup of the soil, including the texture, struc-
ture, consistence, color and other physical, chemical, mineralogical,
and biological properties of the various horizons that make up the
soil profile.
Mottled. Irregularly marked with spots of different colors that vary
in number and size. Mottling in soils usually indicates poor
aeration and lack of drainage. Descriptive terms are as follows:
Abundance--few, common, and many; si ze--f i ne, rnedi urn, and coarse:
and contrast--faint, distinet, and promiTTeTTt. The size measure-
ments are these: fine less than 5 mTl limeters (about 0.2 inch) in
diameter along the greatest dimension; medium, ranging from 5 milli-
meters to 15 millimeters (about 0.2 to 0.6 inch) in diameter, along
the greatest dimension; and coarse, more than 15 millimeters (about
0.6 inch) in diameter along the greatest dimension.
Munsell notation. A system for designating color by degrees of the
three simple variables — hue, value and chroma. For example, a
notation of 10YR 6/4 is a color with a hue of 10YR, value of 6
and a chroma of 4.
Natural drainage. Refers to moisture conditions that existed during the
development of the soil, as opposed to altered drainage, which is
commonly the result^of artificial drainage or irrigation but may be
caused by the sudden deepening of channels or the blocking of drain-
age outlets. Several different class es of natural drainage are
Excessively drained soils are commonly very porous and rapidly
permeable and have a low water-holding capacity.
Somewhat excessively drained soils are also very permeable and
are free from mottling throughout their profile.
Wei1-drained soils are nearly free from mottling and are commonly of
Tntermediate texture.
41
-------
Mp_derate1y we! 1-drai ned soils commonly have a slowly permeable layer
in or immediately beneath the sol urn. They have uniform color in the
A and upper B horizons and have mottling in the lower B and the C
horizons.
Imperfectly or somewhat poorly drained soils are wet for significant
periods but not all the time, ancfin podzolic soils commonly have
•mottlings below 6 to 16 inches, in the lower A horizon and in the
B and C horizons.
Poorly drained soils are wet for long periods and are light gray
and generally mottled from the surface downward, although mottling
may be absent or nearly so in some soils.
Very poorly drained soils are wet nearly all the time. They have a
dark-gray or blacF~surface layer and are gray or light gray, with
or without mottling, in the deeper parts of the profile.
Neutral soil. In practice, a soil having a pH value between 6.6 and 7.3.
Strictly speaking, a soil that has a pH value of 7.0.
Organic matter. A general term for plant and animal material, in or on
the soil, in all stages of decomposition. Readily decomposed organic
matter is often distinguished from the more stable forms that are
past the stage of rapid decomposition.
Organic soil. A general term applied to a soil or to a soil horizon
that consists primarily of organic matter, such as peat soils,
mulch soils, and peaty soil layers. In chemistry, organic refers
to the compounds of carbon.
Pan. A layer in a soil that is firmly compacted or very rich in clay.
Frequently the word "pan" is combined with other words that more
explicitly indicate the nature of the layers; for example, hard-
pan, fragipan, and claypan.
Parent material (soil). The horizon of weathered rock or partly weath-
ered soil material from which soil has formed; horizon C in the
soil profile.
Ped. An individual natural soil aggregate, such as a crumb, a prism,
or a block in contrast to a clod.
Permeability, soil. The quality of a soil horizon that enables water
or air to move through it. Terms used to describe permeability are
as follows: very slow, slow, moderately slow, moderate, moderately
rapid, rapid, and very rapid.
pi-l. A numerical means for designating relatively weak acidity and
alkalinity, as in soils and other biological systems. A pH value
of 7.0 indicates precise neutrality; a higher value, alkalinity; an
and a lower value, acidity.
Phase soil. A subdivision of a soil type, series, or other unit in the
soil classification system made because of differences in the soil
that affect its management but do not affect its classification in
the natural landscape. A soil type, for example, may be divided
42
-------
into phases because of differences in slope, stoniness, thickness or
some other characteristic that affects management.
Physical properties of soils. Properties related to or caused by the
forces and operations of physics.
Plant density. TliC averanc number of plants per area sampled.
Plastic (soil consistence). Capable of being deformed without being
broken.
Plastic limit (soil engineering). The moisture content at which a soil
changes from a solid to a plastic state.
Precipitation-effectiveness (P-E) index. The sum of the 12 monthly
quotients of precipitation divided by the evaporation during the
12 months.
Profile, soil. A vertical section of the soil through all its horizons
and extending into the parent material. See Horizon, soil.
Quartz, Brilliant, crystalline mineral, silicon dioxide, SiO, occurring
in abundance, most often in a colorless, transparent form, but also
sometimes as variously colored semi-precious stones.
Quartzite. Massive hard, light-colored rock with a flinty sheen; it is
a metamorphosed sandstone.
Range (or rangeland). Land that, for the most part, produces native
plants suitable for grazing by livestock; includes land on which
there are some forest trees.
Range condition. The state of health or productivity of both soil and
forage in a given range, in terms of what it could or should be
under normal climate and the best practical management. Condition
classes generally recognized are—excellent, good, fair, and good.
The classification is based on the percentage of original, or climax,
vegetation on the site, as compared to what ought to grow on it if
management were good,
Range plant cover. All the herbaceous and shrubby plants on a range
that livestock can reach, regardless of whether these plants con-
stitute forage.
Range site. An area of range where climate, soil and topography are
sufficiently uniform to produce a distinct kind of climax vege-
tation.
Range survey. A systematic, comprehensive inventory and analysis of the
range resources and the related problems of management, in a range
area, and development of plans for its management.
Range type. An area of range differentiated from other range areas
primarily by its kind of plant cover, such as grass, browse, or
conifer.
Reaction, soil. The degree of acidity or alkalinity of a soil expressed
in pll values. A soil that tests to pH 7.0 is precisely neutral in
reaction, because it is neither acid or alkaline. In words the
degrees of acidity or alkalinity are expressed thus:
43
-------
pri PH
Extremely acid Below 4.5 Neutral 6.6 to 7.3
Very strongly acid 4.5 to 5.0 Mildly alkaline 7.4 to 7.8
Strongly acid 5.1 to 5.5 Moderately alkaline 7.9 to 8.4
Medium acid 5.6 to 6.0 Strongly alkaline 8.5 to 9.0
Slightly acid 6.1 to 6.5 Very strongly alkaline above pH 9.0
Rhyolite. A type of volcanic rock containing much silica and resembling
granite in composition but having a texture that shows flow.
Ridge terrace. A long, low ridge of earth that has gently sloping
sides and a shallow channel along the upper side; controls erosion
by diverting surface runoff across the slope instead of allowing
it to flow uninterrupted down the slope. Compare with Bench terrace.
Rolling. Having moderately steep, complex slopes; intermediate between
undulating and hilly.
Root zone. The part of the soil that is penetrated, or can be penetrated
by plant roots.
Sand. Individual rock or mineral fragments in soils having diameters
ranging from 0.05 to 2.0 millimeters. Most sand grains consist
of quartz, but they may be of any mineral composition. The textural
class name of any soil that contains 85 percent or more sand and
not more than 10 percent clay.
Sandy soils. A broad term for soils of the sand and loamy sand classes;
soil material with more than 70 percent and less than 15 percent
clay.
Sedimentary rock. A rock composed of particles deposited from suspension
in water. The chief sedimentary rocks are conglomerate from gravel,
sands one from sand; shale from clay; and limestone from soft masses
of calcium carbonate. There are many intermediate types. Some wind
deposited sands have been consolidated into sandstone.
Semi-arid climate. A climate intermediate between that of a true desert
and a subhumid area.
Series, soil. A group of soils developed from a particular type of
parent material and having genetic horizons that, except for texture
of the surface soil, are similar in differentiating characteristics
and in arrangement in the profile.
Sesquioxides. Oxides having trivalent cations, as iron or aluminum
oxides.
Shale. A sedimentary rock formed by the hardening of clay deposits.
Sheet erosion. The removal of a fairly uniform layer of soil or material
from the land surface by the action of rainfall and runoff water.
Silica. An important soil constituent composed of silicon and oxygen.
The essential material in the mineral called quartz.
Silica-sesquioxide ratio. The ratio of the number of molecules of
silica to the number of molecules of alumina plus iron oxide in
a soil or the clay fraction of a soil. The more highly weathered
materials in warm-temperate humid regions and especially those in
the tropics, generally have low ratios. The clay in soils with low
ratios normally are less active, physically and chemically than
these with high ratios.
44
-------
Silt, indivuiuui .inneral panicles in a soil Uni range in diameter
from the upper hunt of clay (0.002 millimeters) to tne lower 1 imi t
of very fine sand (0.05 millimeters). Soil of the silt textural
class is 80 percent or more silt and less than 12 percent clay.
Soil map. A map designed to show the distribution of soil mapping units
in relation to the prominent physical and cultural features of tne
earth's surface.
Soil series. Soils qroup having soil horizons similar in differentiating
characteristics and arangement in the soil profile, except for the
texture of the surface soil, and developed from a particular type of
parent material. (The names of the soil series in this report is
tentative.)
Soil separates. Mineral particles, less than 2 millimeters in equivalent
diameter and ranging between specified size limits. The names and
sizes of separates recognized in the United States are as follows:
Very coarse sand (2.0 to 1.0 millimeter); coarse sand (1.0 to 0.5
millimeter); medium sand (0.5 to 1.25 millimeter); fine sand (0.25 to
0.10 millimeter) very fine sand (0.10 to 0.05 to 0.002 millimeter);
and clay (less than 0.002 millimeter). The separates recognized
by the International Society of Soil Science are as follows: I (2.0
to 0.2 millimeters); II (0.2 to 0.02 millimeters); III (0.02 to
0.002 millimeters); IV (less than 0.002 millimeter).
Soil survey. A systematic examination, description, classification,
and mapping of soils in an area. Soil surveys are classified
accordingly to intensity of field examination as exploratory,
reconnaissance, or detailed.
Solum (pi. sola). The upper part of a soil profile, above that parent
material, in which the processes of soil formation are active.
The sol urn in mature soil includes the A and B horizons. Generally,
the characteristics of the material in these horizons are unlike
those of the underlying parent material. The living roots and
other plant and animal life characteristic of the soil are largely
confined to the sol urn.
Stones. Rock fragments greater than 10 inches in diameter if rounded,
and greater than 15 inches along the longer axis if flat.
Stony. Used to describe soils that contain stones in numbers that
interfere with or prevent tillage.
Stratified. Composed of, or arranged in, strata, or layers, such as
stratified alluvium. The term is confined to geological material.
Layers in soil that result from the processes of soil formation
are called horizons; those inherited from the parent material are
called strata.
Structure, soil. The arrangement of primary soil particles into com-
pound particles or clusters that are separate from adjoining
aggregates and have properties unlike those of an equal mass of
unaggregated primary soil particles. The principal forms of soil
structure are platy, (laminated), prismatic, (vertical axis of
45
-------
aggregates longer than horizontal), columnar, (prisms with rounded
tops), blocky, (angular or subanqular), and granular. Structure-
less soils are (l) single grain (each grain by itself as in dune
sand) or (2) massive (the particles adhering together without any
regular cleavage, as in many claypans and hardpans).
Subsoil. Technically, the B horizon; roughly, the part of the profile
below plow depth.
Substratum. Any layer lying beneath the sol urn, or true soil; the C or
D horizon.
Surface layer. A term used in nontechnical soil descriptions for one
or more layers above the subsoil. Includes A horizon and part of
B horizon; has no depth limit.
Surface soil. The soil ordinarily moved in tillage, or its equivalent
in uncultivated soil, about 5 to 8 inches in thickness. The plowed
layer.
Terrace. An embankment, or ridge, constructed-across sloping soils a
the contour or at a slight angle to the contour. The terrace
intercepts surplus runoff so that it may soak into the soil or
flow slowly to a prepared outlet without harm. Terraces intended
mainly for drainage have a deep channel that is maintained in
permanent soil. See also broadbase terrace, narrowbase terrace,
bench terrace.
Terrace (geological). An old alluvial plain, ordinarily flat or un-
dulating bordering a river, lake, or the sea. Stream terraces
are frequently called second bottom, as contrasted to flood plains,
and are seldom subject to overflow. Marine terraces were deposited
by the sea and are generally wide.
Topsoil. A presumed fertile soil or soil material, ordinarily rich in
organic matter used to topdress roadbanks , lawns, and gardens.
Trace elements. The chemical elements found in soils in extremely
small amounts, yet which are essential to plant growth. Some of
the trace elements are zinc, cobalt, manganese, and copper,
Synoynm: Minor elements.
Tuff. Dorous rock, usually stratified, formed by consolidation of
volcanic ashes, dust, etc.
Type, soil. A subdivision of the soil series that is made on the basis
of differences in the texture of the surface layer.
Typic Durorthids. Typic means typical, Dur-orthids mean durable and
orthophoric are combined into the word Durorthids. The duripan
has an upper boundary within 40 inches of the surface.
Value (color). One of three variables of color. Value increases as
the relative intensity of reflected light increases. See Munsell
notation.
46
-------
DISTRIBUTION
1 - 20 WERL, Las Vegas, Nevada
21 Robert E. Miller, Manager, NVOO/AEC, Las Vegas, Nevada
22 Robert H. Thalgott, NVOO/AEC, Las Vegas, Nevada
23 A. Dean Thornbrough, NVOO/AEC, Las Vegas, Nevada
24 Henry G. Vermillion, NVOO/AEC, Las Vegas, Nevada
25 Donald W. Hendricks, NVOO/AEC, Las Vegas, Nevada
26 Elwood M. Douthett, NVOO/AEC, Las Vegas, Nevada
27 Jared 0. Davis, NVOO/AEC, Las Vegas, Nevada
28 Ernest D. Campbell, NVOO/AEC, Las Vegas, Nevada
29 - 30 Technical Library, NVOO/AEC, Las Vegas, Nevada
31 Chief, NOB/DASA, NVOO/AEC, Las Vegas, Nevada
32 Joseph J. DiNunno, Office of Environmental Affairs, USAEC, Washington, D.C.
33 Martin B. Biles, DOS, USAEC, Washington, D.C.
34 Roy D. Maxwell, DOS, USAEC, Washington, D.C.
35 Assistant General Manager, DMA, USAEC, Washington, D.C.
36 Gordon C. Facer, DMA, USAEC, Washington, D.C.
37 John S. Kelly, DPNE, USAEC, Washington, D.C.
38 Fred J. Clark, Jr., DPNE, USAEC, Washington, D.C.
39 John R. Totter, DBM, USAEC, Washington, D.C.
40 John S. Kirby-Smith, DBM, USAEC, Washington, D.C.
41 L. Joe Deal, DBM, USAEC, Washington, D.C.
42 Charles L. Osterberg, DBM, USAEC, Washington, D.C.
43 Rudolf J. Engelmann, DBM, USAEC, Washington, D.C.
44 Philip W. Allen, ARL/NOAA, Las Vegas, Nevada
45 Gilbert J. Ferber, ARL/NOAA, Silver Spring, Maryland
46 Stanley M. Greenfield, Assistant Administrator for Research & Monitoring,
EPA, Washington, D.C.
47 Joseph A. Lieberman, Deputy Assistant Administrator for Radiation Programs,
EPA, Rockville, Maryland
48 Paul T. Tompkins, Act.Dir., Div. of Criteria & Standards, Office of
Radiation Programs, EPA, Rockville, Md.
-------
Distribution(continued)
49 - 50 Charles L. Weaver, Act.Dir., Office of Radiation Programs, Div. of
Surveillance & Inspection, EPA, Rockville, Md.
51 Ernest D. Harward, Div. of Technology Assessment, Office of Radiation
Programs, EPA, Rockville, Md.
52 William A. Mills, Act.Dir.s Div. of Research, Office of Radiation
Programs, EPA, Rockville, Md.
53 Bernd Kahn, Radiological Engineering Lab., EPA, Cincinnati, Ohio
54 Interim Regional Coordinator, Region IX, EPA, San Francisco, Calif.
55 Eastern Environmental Radiation Laboratory, EPA, Montgomery, Alabama
56 William C. King, LRL, Mercury, Nevada
57 Bernard W. Shore, LRL, Livermore, California
58 James E. Carothers, LRL, Livermore, California
59 Roger E. Batzel, LRL, Livermore, California
60 Howard A. Tewes, LRL, Livermore, California
61 Lawrence S. Germain, LRL, Livermore, California
62 Paul L. Phelps, LRL, Livermore, California
63 William E. Ogle, LASL, Los Alamos, New Mexico
64 Harry J. Otway, LASL, Los Alamos, New Mexico
65 George E. Tucker, Sandia Laboratories, Albuquerque, New Mexico
66 Wright H. Langham, LASL, Los Alamos, New Mexico
67 Harry S. Jordan, LASL, Los Alamos, New Mexico
68 Arden E. Bicker, REECo., Mercury, Nevada
69 Clinton S. Maupin, REECo., Mercury, Nevada
70 Byron F. Murphey, Sandia Laboratories, Albuquerque, New Mexico
71 Melvin L. Merritt, Sandia Laboratories, Albuquerque, New Mexico
72 Richard S. Davidson, Battelle Memorial Institute, Columbus, Ohio
73 R. Glen Fuller, Battelle Memorial Institute, Las Vegas, Nevada
74 Steven V. Kaye, Oak Ridge National Lab., Oak Ridge, Tennessee
75 Leo K. Bustad, University of California, Davis, California
76 Leonard A. Sagan, Palo Alto Medical Clinic, Palo Alto, California
77 Vincent Schultz, Washington State University, Pullman, Washington
78 Arthur Wallace, University of California, Los Angeles, California
79 Wesley E. Niles, University of Nevada, Las Vegas, Nevada
80 Robert C. Pendleton, University of Utah, Salt Lake City, Utah
-------
Distribution(concluded)
81 William S. Twenhofel, U.S. Geological Survey, Denver, Colorado
82 Paul R. Fenske, Teledyne Isotopes, Palo Alto, California
83 - 84 DTIE, USAEC, Oak Ridge, Tennessee (for public availability)
------- |