John Fisher Senior Regional Soil Scientist

775 857-8500 ext 127 john.fisher@nv.usda.gov

What is soil Soil is a natural body comprised of solids (minerals and organic matter), liquid,

and gases that occurs on the land surface, occupies space, and is characterized by one or both of the following: horizons, or layers, that are distinguishable from the initial material as a result of additions, losses, transfers, and transformations of energy and matter or the ability to support rooted plants in a natural environment.

The upper limit of soil is the boundary between soil and air, shallow water, live plants, or plant materials that have not begun to decompose. Areas are not considered to have soil if the surface is permanently covered by water too deep (typically more than 2.5 meters) for the growth of rooted plants.

The lower boundary that separates soil from the nonsoil underneath is most difficult to define. Soil consists of horizons near the earth's surface that, in contrast to the underlying parent material, have been altered by the interactions of climate, relief, and living organisms over time. Commonly, soil grades at its lower boundary to hard rock or to earthy materials virtually devoid of animals, roots, or other marks of biological activity. For purposes of classification, the lower boundary of soil is arbitrarily set at 200 cm.

A History of Soil Survey in Nevada A compilation of short stories commemorating the 100th

Anniversary of the Soil Survey Program Compiled by Paul W. Blackburn MLRA Leader in Elko,

NV July 2000 Publication available under soils at

http://www.nv.nrcs.usda.gov/

Present Status Official soil surveys on Web Soil Survey at http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm or at Soil Data Mart http://soildatamart.nrcs.usda.gov/ Published copies are outdated but still can be useful

Foreseeable Priorities for Nevada Soils 1. Complete the mapping of Federal Lands. 2. Updates of soil data and soil lines by MLRAs 3. Soil data in the National Soil Information System (NASIS) will

be “harmonized”. (3 year projects) 4. Official series descriptions OSDs will be edited to be metric and

to be located by longitude and latitude in NAD 83 (field verified).

5. Benchmark soils will be emphasized. 6. Continue collecting and add sites for soil temperature data. 7. Sample temperature sites for lab data. 8. Soils support for state and transition modeling and ecological

site development.

Scan Site Porter Canyon

Benchmark Soils A Benchmark soil is one that is selected to represent a

number of other soils. Criteria used: Large extent Key taxonomic Class Existing data (laboratory information) Other considerations Major parent material Major landform Ecological importance Significant land uses

GIS Tools for Nevada Soils Map Unit Description Report developed by Lucas Wisely

which verifies: landforms, component percents, slopes, precipitation, temperature and elevations.

ArcSIE (Soils Inference Engine) will be used to model

probable locations for components and possible ecological site locations - used for premapping and to compare predicted component locations with mapped component locations.

Mapping Concepts “Soil mapping is possible only because men can examine

a profile at one point and successfully predict its occurrence at another point where surface indications are similar.” - Author unknown.

0r “Soil mapping is possible because of observable

discontinuities between landscape units and a strong relation between landscape units and soils. These relationships make it possible to accurately delineate bodies of soil with limited observations. “ Hudson.

Procedure for Mapping Soils Prediction - mapping concept

Validation - check prediction

Compromise – same use and management -same

interpretations

Documentation and Consistency – extremely important for updates

Prediction

Concepts for Soil Prediction Five soil forming factors Use of the soil-landscape model Conceptualize soil individuals and natural bodies of soils

on the landscape. Use of vegetation to predict soil properties Repeatable patterns Implicit or Tacit knowledge - experience

Five Soil Forming Factors Parent Material (geology, depositional history) Climate (rainfall, temperature) Relief or Topology (slope, aspect, geomorphology) Biological Factors (plants, animals, microbes and Us) Time (geomorphology, stability)

Natural Bodies of Soils on the Landscape. A map unit is a collection of areas defined and named

the same in terms of their soil components or miscellaneous areas or both. Each map unit differs in some respect from all others in a survey area and is uniquely identified on a soil map. Each individual area on the map is a delineation.

Landscape is used to describe the map unit general appearance for example, mountains, hills, piedmont slopes, fan piedmonts, basin floors, bolson floors, and semi-bolson flooors

Conceptualize soil individuals Soil Series-the lowest category of the national soil

classification system. Nationally there are about 22,000 series recognized and

about 2,000 originated in Nevada. Soil Series are defined by Official Soil Series Descriptions

contain soil properties that define the soil series, distinguish it from other soil series, serve as the basis for the placement of that soil series in the soil family, and provide a record of soil properties needed to prepare soil interpretations.

Soil series or phase is a component of the map unit and is located by a landform.

Pyropatti Series

Consociations Delineated areas are dominated by a single soil taxon

usually a soil series or miscellaneous area and similar soils with no more than 15 percent contrasting components (inclusions).

Name includes surface texture and usually slope Used mostly in order II soil mapping.

Complexes and Associations Complexes and associations consist of two or more

dissimilar components (usually soil series) occurring in a regularly repeating pattern with no more than 15 percent contrasting components (inclusions).

Complex-major components cannot be mapped separately at a scale of about 1:24,000 .

Association- major components can be separated at a scale of about 1:24,000

Used mostly in order III soil mapping.

Use of the soil-landscape model Landforms of the Basin and Range Province By Fredrick

F Peterson January 1981 Publication available under soils at

http://www.nv.nrcs.usda.gov/ A landform is a three-dimensional part of the general

land surface which is distinctive and recognizable because it has some significance to people and repeats across the landscape in a fairly consistent position with respect to surrounding landforms.

Fan remnants and inset fans on fan piedmonts with hills in background

Plants Used to Predict Some of the Soil Properties in the Great Basin Soil depth: type of sagebrush, height of sagebrush, amount of

mature trees, amount of large young trees. Soil color: type of sagebrush, height of sagebrush, Antelope

bitterbrush, amount of bluebunch wheatgrass, amount of mature trees

Organic matter: type of sagebrush, height of sagebrush,

Antelope bitterbrush, amount of bluebunch wheatgrass, amount of mature trees.

Depth to water table: black greasewood, saltgrass, rushes and

sedge, cattails, cottonwood, willows (types), salt cedar, silver sage.

Soil texture: types of sagebrush, winterfat, Indian ricgrass, galleta, fourwing saltbush, Nevada dalea, four-part horsebrush

Carbonates: black sagebrush, littleleaf mahogany, winterfat. Soil temperature-creosote bush, Idaho fescue, Idaho fescue, antelope

bitterbush, mountain big sagebrush, white bur sage. Horizon boundary: type of sagebrush. Soil pores: shadscale, Bailey greasewood, spiny mendora, sagebrush Effective soil moisture: shadscale, sagebrush, singleleaf pinyon,

antelope bitterbrush, Bailey’s greasewood, snowberry, bluebunch wheatgrass

Tacit Knowledge Tacit knowledge is gained by experience. Soil-landscape concept is extremely dependant on tacit

knowledge. Difficult to pass this tacit knowledge to newer soil

scientists.

Potential and Actual Retirement of Tacit Knowledge

Verification

Soil Contacts Reno State Office/MO-03 Office (775) 857-8500 Levi Steptoe, State Soil Scientist/MO-03 Leader ext. 120 levi.steptoe@nv.usda.gov

Tom Champa, Soil Data Quality Specialist ext. 122 tom.champa@nv.usda.gov Lucas Wiseley, GIS Specialist ext. 126 lucas.wisely@nv.usda.gov Erin Hourihan, Range Management Specialist ext. 130 erin.hourihan@nv.usda.gov

Elko MLRA Office: (775) 738-8431

Paul Blackburn, MLRA leader ext. 122 paul.blackburn@nv.usda.gov Nathan Lurie, Soil Scientist ext. 129 nathan.lurie@nv.usda.gov

Ely MLRA Office: (775) 289-4065

Curt Leet, Soil Scientist ext. 108 curt.leet@nv.usda.gov Brien Park, Soil Scientist ext.111 brien.park@nv.usda.gov

Minden MLRA office: (775) 782-3661

Ed Blake, MLRA leader ext. 110 ed.blake@nv.usda.gov Matt Cole, Soil Scientist ext. 103 matt.cole@nv.usda.gov

Steve Herriman, Resource Soil Scientist ext. 109 steve.herriman@nv.usda.gov

Las Vegas Office (702) 262-9047 Doug Merkler, Resource Soil Scientist ext 106 doug.merkler@nv.usda.gov

But it Feels Like . . .

It is all sand, silt & clay

Textural Triangle

Trust me – it is all sand, silt or clay

But it looks like ….