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MESA COUNTY AREA, COLORADO
<br />Youngston Series
<br />The Youngston series consists of deep, well-drained
<br />soils. These soils formed in alluvium on flood plains
<br />and alluvial fans. The slope is 0 to 3 percent, and ele-
<br />vation is 4,800 to 5,400 feet. The natural vegetation is
<br />mainly saltbush, rabbitbrush, galleta, and Indian rice-
<br />grass. The average annual precipitation is 9 inches.
<br />The mean annual temperature is 520 F., and the frost-
<br />free season is 160 to 175 days.
<br />In a representative profile the surface layer is light-
<br />gray loam about 4 inches thick. The underlying layers
<br />are light brownish-gray sandy loam, very pale brown
<br />loam, and pale-brown very fine sandy loam and loam
<br />that extend to a depth of 60 inches or more.
<br />. Youngston soils have moderate permeability and a
<br />high available water capacity. They are moderately al-
<br />kaline. Roots can penetrate to a depth of more than 60
<br />inches.
<br />These soils are used for grazing, as wildlife habitat,
<br />and as watershed areas.
<br />Representative profile of Youngston loam, NWl/4
<br />sec. 9, T. 2 N., R. 2 W., in an area of grass.
<br />A1-0 to 4 inches, li ht -gray (10YR 7/2) loam, dark gray-
<br />ish brown flOYR 4/2) moist; weak, thin, platy
<br />parting to weak, fine, granular structure; soft,
<br />very friable; calcareous; moderately alkaline;
<br />clear, smooth boundary.
<br />AC-4 to 8 inches, light brownish-gray (10YR 6/2) sandy
<br />loam, dark grayish brown (10YR 4/2) when
<br />moist; weak, thin, platy parting to weak, fine,
<br />granular structure; loose, very friable; calcare-
<br />ous; clear, smooth boundary.
<br />CI-8 to 20 inches, very pale brown (10YR 7/3) loam,
<br />brown (10YR 5/3) when moist; weak, fine, sub-
<br />angular blocky parting to weak, fine, granular
<br />structure • slightly hard, friable, calcareous; mod-
<br />erately alkaline; clear, smooth boundary.
<br />C2-20 to 38 inches, pale-brown (10YR 6/3) very fine
<br />sandy loam, dark brown (10YR 4/3) when moist;
<br />weak, fine, subangular blocky parting to weak, fine,
<br />granular structure; slightly hard, friable; calcar-
<br />C3-38 to 60 nchesa pale brown ;(10YR 6/3)t loam, l dark
<br />brown (10TR 4/3) when moist; massive- hard
<br />when dry, very friable when moist; calcareous;
<br />moderately alkaline.
<br />The Al is loam or very fine sandy loam. Coarse frag-
<br />ments make up as much as 15 percent, by volume, but com-
<br />monly less than 5 percent of the soil.
<br />Yo-Youngston loam. This soil is nearly level and
<br />is on flood plains and alluvial fans. It has the profile
<br />described as representative of the series.
<br />Included with this soil in mapping are areas of
<br />Billings soils.
<br />. Runoff is slow to moderate. The hazard of erosion is
<br />moderate.
<br />This soil is used mainly for grazing and as wildlife
<br />habitat. Capability unit VIe-1; Loamy Salt Desert
<br />range site.
<br />Use and Management of the Soils
<br />The soils in the Mesa County Area are used mainly
<br />for range. A small acreage is used for irrigated pas-
<br />ture, hay, and crops. This section discusses these uses
<br />and the suitability of the soils for roads, farm ponds,
<br />and other engineering structures. It also provides in-
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<br />formation on managing the soils for several land uses
<br />and for wildlife habitat.
<br />Crops, Hay, and Pasture
<br />The small acreage used for irrigated crops, hay, and
<br />pasture makes up less than 0.1 percent of the Mesa
<br />County Area. The main crops are barley, oats, and
<br />corn. Pasture and hay plantings are mainly alfalfa or
<br />a mixture of alfalfa or clover and brome or fescue
<br />grasses.
<br />Estimated yields of crops are given in the discussion
<br />of individual capability units on the following pages.
<br />The range of yields given are those that can be ex-
<br />pected from a reasonably high level of management
<br />which includes the :following:
<br />1. Using cropping systems that maintain good
<br />tilth and a high content of organic matter.
<br />2. Controlling erosion to the maximum extent
<br />feasible, so that the quality of the soil is main-
<br />tained or improved.
<br />3. Maintaining; a high level of fertility by using
<br />fertilizer ir.' amounts recommended by the
<br />Colorado Agricultural Experiment Station.
<br />4. Using crop residues to the fullest extent prac-
<br />ticable to protect and improve the soil.
<br />5. Following minimum tillage practices to re-
<br />duce soil compaction and erosion.
<br />6. Using adapted crop varieties.
<br />7. Controlling weeds by tillage.
<br />Capability Grouping
<br />Capability groupin;? shows, in a general way, the
<br />soiuitability of soils fo:r most kinds of field crops. The
<br />sls are grouped according to their limitations when
<br />used for field crops, the risk of damage when they are
<br />used, and the way they respond to treatment. The
<br />grouping does not take into account major and gen-
<br />erally expensive landforming that would change slope,
<br />depth, or other characteristics of the soils; does not
<br />take into consideration, possible but unlikely major rec-
<br />lamation projects; and, does not apply to horticultural
<br />crops or other crops requiring special management.
<br />Those familiar with the capability classification can
<br />infer from it much about the behavior of soils when
<br />used for other purposes, but this classification is not a
<br />substitute for interpretations designed to show suit-
<br />ability and limitations of groups of soils for range or
<br />engineering.
<br />In the capability system, the kinds of soil are
<br />grouped at three levels : the capability class, the sub-
<br />class, and the unit. These are discussed in the follow-
<br />ing paragraphs.
<br />CAPABILITY CLASSES, the broadest groups, are des-
<br />ignated by Roman numerals I through VIII. The nu-
<br />merals indicate progressively greater limitations and
<br />narrower choices for practical use, defined as follows :
<br />Class I soils have few limitations that restrict
<br />their use. i
<br />Class II soils have moderate limitations that re-
<br />duce the choice of plants or that require mod-
<br />erate conservation practices.
<br />Class III soils have severe limitations that reduce
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