WSP00003

• File Number: 8200.760
• Description: Yampa River General
• State: CO
• Basin: Yampa/White
• Water Division: 6
• Date: 4/1/1969
• Author: CWCB - USDA
• Title: Water and Related Land Resources - Yampa River Basin - Colorado and Wyoming
• Water Supply Pro - Doc Type: Report/Study

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Yampa, and Little Snake rivers and Vermilion and Muddy creeks. A
significant body of playas interspersed with hummocks and low sandhi lIs
extends from east of Kenney Rim in Wyoming to beyond Sand Creek. Very
steep and intricately dissected shale badlands are scattered within the
unit both in Colorado and Wyoming.

Surface soils are light colored, relatively low in organic matter and
range in texture from loamy sand to silty clay. Subsoils are principally
sandy loam, clay loam or clay in texture and have a rapid to slow perme-
ability rate. Sandy subsoils with a rapid permeability are a minor
component. Generally, these soils have an alkaline reaction and are limy
at or within a few inches of the surface.

Some soils on fans and terraces are very strongly alkaline in reaction
ar.d high in exchangeable sodium as evidenced by scattered "slick spots"
that are devoid of vegetation. Injurious accumulations of soluble salt
are largely restricted to bottomland soils and areas bordering shale
badlands.

Soil Mapping Unit 2.0: Moderately dark colored soils of the uplands and
valleys

These soils are separated into four separate units on the map that differ
in proportions of different kinds of soil and on the map they are shown
as 2.1, 2.2, 2.3, and 2.4. They are all dominated by moderately dark
colored soils and occupy sagebrush and pinyon-juniper lands in the foot-
hill transition between deserts and mountains. Moisture conditions are
more favorable for plant growth than in the desert but cropping of non-
irrigated land is limited by the low annual precipitation.

Soil Mapping Unit 2.1: Shallow rocky or gravelly soils with associated
deep soils

There is only one delineation of this unit in Wyoming but there are three
in Colorado. It is mainly confined to western Moffat County. The unit
encompasses steep gravelly slopes and rocky ledges covered with scattered
pinyon-juniper. Associated with the steep slopes are higher-lying moder-
ately sloping sagebrush uplands. The landscape is highly dissected by
intermittent stream channels.

The most intensive component of unit 2.1 is shallow gravelly or stony
soils. They overlie sandstone or shale at depths of 20 inches and are
usually calcareous. At many locations the soft sandstone is penetrated
by tree roots. Deeper soils that have high proportions of coarse frag-
ments in the subsoil occupy footslope positions within complex patterns
of shallow soils. Deep, moderately dark colored loamy soils that are
noncalcareous to depths of 6 to 24 inches occupy smoother slopes on the

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