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6.4.9 Exhibit i -Soils Information
<br />WELD COUNTY, COLORADO, SOUTHERN PART
<br />attracted by developing livestock watering facilities,
<br />m~ng livestock grazing and reseeding where needed.
<br />soil has good potential for urban development. The
<br />only limiting feature is the moderately rapid permeability
<br />in the substratum, which causes a hazard of ground water
<br />contamination from sewage lagoons. The loamy sand sur-
<br />face layer is a limitation for recreational development.
<br />Once established, the lawns, shrubs, and trees grow well.
<br />Capability subclass IIIe irrigated, IVe nonirrigated;
<br />Sandy Plains range site.
<br />95-Olney loamy sand, 3 to 5 percent slopes. This is a
<br />deep, well drained soil on plains at elevations of 4,600 to
<br />5,200 feet. It formed in mixed outwash deposits. Included
<br />in mapping are small areas of soils that have sandstone
<br />and shale within a depth of 60 inches and some small
<br />leveled areas.
<br />Typically the surface layer of this Olney soil is grayish
<br />brown loamy sand about 7 inches thick. The subsoil is yel-
<br />loNrish brown and very pale brown sandy clay loam about
<br />14 inches thick. The substratum to a depth of 60 inches is
<br />very pale brown, calcareous fine sandy loam.
<br />Permeability and available water capacity are
<br />moderate. The effective rooting depth is 60 inches or
<br />more. Surface runoff is slow, and the erosion hazard if
<br />IOw.
<br />In irrigated areas this soil is suited to the crops com-
<br />monly grown in the area. Perennial grasses and alfalfa or
<br />close grown crops should be grown at ]east 50 percent of
<br />the time. Close grown crops and pasture can be irrigated
<br />w~ontour ditches and corrugations. Furrows, contour
<br />fu s, and cross slope furrows are suitable for row
<br />emps. Sprinkler irrigation is also desirable. Keeping'til-
<br />lage to a minimum and utilizing crop residue help to con-
<br />trol erosion. Maintaining fertility and organic matter con-
<br />tent is important. Crops respond to barnyard manure and
<br />commercial fertilizer.
<br />The potential native vegetation on this range site is
<br />dominated by sand bluestem, sand reedgrass, and blue
<br />grama. Needleandthread, switchgrass, sideoats grama,
<br />and western wheatgrass are also prominent. Potential
<br />production ranges from 2,200 pounds per acre in favora-
<br />ble years to 1,800 pounds in unfavorable years. As range
<br />condition deteriorates, the sand bluestem, sand reedgrass,
<br />and switchgrass decrease and blue grama, sand dropseed,
<br />and sand sage increase. Annual weeds and grasses invade
<br />the site as range condition becomes poorer.
<br />Management of vegetation on this soil should be based
<br />~n taking half and leaving half of the total annual produc-
<br />tion. Seeding is desirable if the range is in poor condition.
<br />Sand bluestem, sand reedgrass, switchgrass, sideoats
<br />srama, blue grama, pubescent wheatgrass, and crested
<br />wheatgrass are suitable for seeding. The grass selected
<br />should meet the seasonal requirements of livestock. IC can
<br />oe seeded into clean, firm sorghum stubble, or it can be
<br />irilled into a firm prepared seedbed. Seeding early in
<br />'pang has proven most successful.
<br />Windbreaks and environmental plantings are generally
<br />;into this soil. Soil blowing, the principal hazard in
<br />31
<br />establishing trees and shrubs, can be controlled by cul-
<br />tivating only in the tree row and by leaving a strip of
<br />vegetation between the rows. Supplemental irrigation
<br />may be needed at the time of planting and during dry
<br />periods. Trees that are best suited and have good survival
<br />are Rocky Mountain juniper, eastern redcedar, ponderosa
<br />pine, Siberian elm, Russian-olive, and hackberry. The
<br />shrubs best suited are skunkbush sumac, lilac, and Siberi-
<br />an peashrnb.
<br />Wildlife is an important secondary use of this soil. The
<br />cropland areas provide favorable habitat for ring-necked
<br />pheasant and mourning dove. Many nongame species can
<br />be attracted by establishing areas for nesting and escape
<br />cover. For pheasants, undisturbed nesting cover is essen-
<br />tial and should be included in plans for habitat develop-
<br />ment, especially in areas of intensive agriculture. Range-
<br />land wildlife, for example, the pronghorn antelope, can be
<br />attracted by developing livestock watering facilities,
<br />managing livestock grazing, and reseeding where needed.
<br />This soil has good potential for urban development. The
<br />only limiting feature is the moderately rapid permeability
<br />in the substratum, which causes a hazard of ground water
<br />contamination from sewage lagoons. The loamy sand sur-
<br />face layer is a limitation for recreational development.
<br />Once established, the lawns, shrubs, and trees grow well.
<br />Capability subclass IIIe irrigated, VI nonirrigated; Sandy
<br />Plains range site.
<br />. 96-Olney fine sandy loam, 0 to 1 percent slopes.
<br />This is a deep, well drained soil on smooth plains at eleva-
<br />tions of 4,600 to 5,200 feet. It formed in mixed outwash
<br />deposits. Included in mapping are small areas of soils that
<br />have a dark. surface layer and some small leveled areas.
<br />Typically the surface layer of this Olney soil is grayish
<br />brown fine sandy loam about 10 inches thick. The subsoil
<br />is yellowish brown and very pale brown sandy clay loam
<br />about 15 inches thick. The substratum to a depth of 60
<br />inches is very pale brown, calcareous fine sandy loam.
<br />Permeability and available water capacity are
<br />moderate. The effective rooting depth is 60 inches or
<br />more. Surface runoff is slow, and the erosion hazard is
<br />]ow.
<br />This soil is used almost entirely for irrigated crops. It
<br />is suited to all crops commonly grown in the area, includ-
<br />ing corn, sugar beets, beans, alfalfa, small grain, potatoes,
<br />and onions. An example of a suitable cropping system is 3
<br />to 4 years of alfalfa followed by corn, corn for silage,
<br />sugar beets, small grain, or beans. Few conservation pra~-
<br />tices are needed to maintain top yields.
<br />All methods of irrigation are suitable, but furrow ir-
<br />rigation is the most common. Barnyard manure and com-
<br />mercial fertilizer are needed for top yields.
<br />Windbreaks and environmental plantings are generally
<br />suited to this soil. Soil blowing, the principal hazard in
<br />establishing trees and shrubs, can be controlled by cul-
<br />tivating only in the tree row and by leaving a strip of
<br />vegetation between the rows. Supplemental irrigation
<br />may be needed at the time of planting and during dry
<br />periods. Trees that are best suited and have good survival
<br />
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