|
PHILLIPS COUNTY, COLORADO
<br />kI, -0 to 5 inches, grayish-brown (10YR 5/2) loam, very dark
<br />grayish brown (10YR 3/2) when moist; weak, thin to
<br />very thick, platy structure that breaks to weak, fine
<br />granular ; hard when dry, friable when moist ; non-
<br />calcareous ; abrupt, smooth boundary.
<br />P1-5 to 9 inches, dark grayish-brown (10YR 4/2) loam, very
<br />(lark grayish brown (10YR 3/2) when moist; moder-
<br />ate, coarse, subangular blocky structure that breaks
<br />to moderate, medium, subangular ; slightly hard when
<br />dry, firm when moist ; noncalcareous ; about 2 percent
<br />fine gravel ; clear, smooth boundary.
<br />B21t-0 to 14 inches, dark gr,iyish-brown (10YR, 4/2) clay
<br />loam, very (lark gray. h brown (10YR 3/2) when
<br />moist ; moderate, mec..am, prismatic structure that
<br />breaks to moderate, fine, subangular blocky ; hard
<br />when dry, friable when moist; noncalcareous; very
<br />thin, patchy clay films ; clear, smooth boundary.
<br />L'22tb-14 to 23 inches, dark-gray (10YR 4/1) silty clay loam,
<br />very dark brown (10YR 2/2) when moist; strong,
<br />medium, prismatic structure that breaks to strong,
<br />fine, subangular blocky ; hard when dry, firm when
<br />moist ; noncalcareous ; thick, nearly continuous clay
<br />films ; gradual, smooth boundary.
<br />133cab-23 to 20 inches, pale-brown (10YR 0/3) silty clay
<br />loam, dart: brown (10YR 4/3) when moist ; moderate,
<br />medium, prismatic structure that breaks to moderate,
<br />medium, subang filar blocky ; slightly hard when dry,
<br />friable when moist ; strongly calcareous ; visible lime
<br />along cleavage lines ; abort 5 percent of the horizon
<br />is very dark grayish brown (10YR 3/2) when moist;
<br />clear, wavy boundary.
<br />C,lea-20 to 43 inches, very pale brown (IOYR 8/3) loam, pale
<br />brown (10YR 0/3) when moist; moderate, medium,
<br />prismatic structure that breaks to moderate, medium,
<br />subangular blocky ; slightly hard when dry, very fri-
<br />able when moist ; very strongly calcareous ; lime prom-
<br />inent, but lower part of horizon contains less lime than
<br />upper part; about 2 percent fine gravel ; clear, wavy
<br />boundary,
<br />('2-43 to 00 inches, very pale brown (10YR 8/3) silt loam,
<br />very pale brown (10YR 7/3) when moist; massive
<br />(structureless) ; hard when dry, friable when moist;
<br />very strongly calcareous.
<br />The,k horizon ranges froin 5 to S inches in thickness, and the
<br />B2t horizon ranges from 10 to 20 inches iu thickness. When
<br />moist the B22tb horizon is black to very dark brown. Depth
<br />to lime ranges from 22 to 3S inches. In some areas a gravel bed
<br />underlies the loess at a depth of 40 inches or more.
<br />Rago soils are associated with the Iiuma and Richfield soils.
<br />In contrast to Richfield soils, Rago soils have a black to dark-
<br />brown layer in the subsoil and are deeper to the limy sub-
<br />stratum. Rago soils have a more clayey B2t horizon than the
<br />Iiuma soils.
<br />Rago and Kuma loams (0 to 3 percent slopes) (Rc) are
<br />in broad areas of the uplands. These soils are so similar
<br />that it is not practical to map them separately. This inap-
<br />wil'g unit is the most extensive one in Phillips County.
<br />1re.ls generally extend in a southeast direction and range
<br />i)mi 40 to 400 acres in size. About 70 percent of the unit is
<br />R':14-0 soil, and 30 percent is E ulna soil, but some fields are
<br />all .Rago soil, and others are ill Kum;ti soil.
<br />Included in mapping were small areas of Platne.r, Rich-
<br />Ji(Ad, and Dawes soils. The Platner soil is in the western
<br />[part of the county, the Richfield soil is in the eastern part,
<br />11.1111 the Dawes soil is in both the central and western parts.
<br />Also included were areas of soil that is similar to Rago
<br />Main, except that gravelly material is at a depth of about
<br />24 inches. Malnv small intermittent lakes or potholes are
<br />Witlliii mapped areas and are shown on the soil map by a
<br />s l)ibol.
<br />Rago and Iiuma loams absorb water at a moderate to
<br />slow rate, and runoff causes erosion during some storms.
<br />These soils have high available moisture capacity.
<br />19
<br />Almost all the acreage is cultivated. The soils in this
<br />group are well suited to winter wheat, barley, sorghums,
<br />and corn that are Cary farmed. They also are suited to many
<br />kinds of irrigated crops. In dryfarmed fields, the practice
<br />of following small grain or sorghum with summer fallow
<br />helps in maintaining soil moisture and fertility. Stubble
<br />mulching and working crop residue into the soil are prac-
<br />tices nee5ed for controlling erosion.
<br />In irrigated fields the soils can be leveled so that the
<br />water spreads uniformly. The crops respond well if fer-
<br />tilizer is added. Working crop residue into the soil helps
<br />to control erosion and to maintain fertility and tilth. Blue
<br />grama, western wheatgrass, and similar grasses grow well
<br />where these soils are used as range. Capalility units IIc-1
<br />(drylancl) and IIe-2 (irrigated) ; Loamy Plains range
<br />site, windbreak suitability group 1.
<br />Richfield Series
<br />The Riclifield series consists of deep, Nvell-drained,
<br />loamy soils of the uplands. These soils occur mainly in the
<br />northeastern part of the county and are nearly level to
<br />moderately sloping.
<br />In a typical profile the surface layer is grayish-brown
<br />loam about G inches thick. It is easily worked.
<br />The subsoil, about 14 inches thick, is noncalcareous. It is
<br />grayish-brown, hard clay loam in the upper part, slightly
<br />hard, dark grayish-brown clay loam in the iniddle part,
<br />and slightly hard, light brownish-gray loans in the. lower
<br />part.
<br />Underlying the subsoil is very pale brown loans or very
<br />fine sanely loam that was deposited by wind and then re-
<br />worked locally by wind and water. The underlying mate-
<br />rial is very strongly calcareous or strongly calcareous. It
<br />contains inuch accumulated lime.
<br />Runoff is medium where slopes are nearly level, but it is
<br />rapid where they are gently sloping or moderately sloping.
<br />The available water holding capacity and natural fertility
<br />are high.
<br />Most of the acreage of Richfield soils is cultivated. These
<br />soils are suited to winter wheat and sorghums. The native
<br />vegetation consists mostly of western wheatgrass and blue
<br />gralina, but some buffalograss grows in depressional areas
<br />where more clay has accumulated in the subsoil. Snake-
<br />-weed is a c•omnnon perennial weed where the native grasses
<br />have been overgrazed.
<br />Typical profile of Richfield loam, 0 to 3 percent slopes,
<br />in a cultivated wheatfield (530 feet east, 2,540 feet north of
<br />the. southwest corner of section 23, T. 9 __.) R. 43 W.) :
<br />Ap-0 to 0 inches, „grayish-brown (10YR 5/2) loam, very dark
<br />;grayish brown (10YR 3/2) when moist; weak, fine,
<br />.granular structure ; soft when dry, very friable when
<br />moist ; noncalcareous ; clear, smooth boundary.
<br />131-0 to 10 inches, grayish-brown (JOYR 5/2) clay loam, very
<br />dark grayish brown (10YR 3/2) when moist; weak,
<br />coarse, prismatic structure that breaks to weak, coarse,
<br />subangular blocky; hard when dry, firm when moist;
<br />very thin, patchy clay films on vertical and horizontal
<br />faces of peels ; noncalcareous ; clear, smooth boundary.
<br />B2t-10 to 15 inches, (lark grayish-brown (10YR 4/2) clay
<br />loam, very (lark grayish brown (10YR 3/2) when
<br />moist; moderate, medium. prismatic structure that
<br />breaks to moderate, medium and fine, subangular
<br />blocky ; slightly hard when dry, firm when moist :
<br />thick, continuous clay films on vertical and horizontal
<br />faces of peels ; noncalcareous ; clear, smooth boundary.
|