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' SOILS 1 t 1 LJ 1 1 1 Lflam}• Alluvial Land Loamy alluvial land, moderately wet ILw) is in many dreinagewavs throughout the county, It is predominantly in the broader drnmagetcnys that have a high water table and that formerly had poor drainage. The areas are broad in the lamer and more early sloping drain- sgewa}•s, especia:ly rn the South ~latte River bottom. All are subject to damage, in varying degrees, by flood- ing from adjacent slopes and mein stream channels. Included in mapping are small areas of Nunn loam, Satanta loam, Net alluvial land, qnd Loamy alluvial land, gravelly substratum. 'Thr soils :n•r moderatel} derp, ranging from ~0 to 36 inches in depth, over unconsolidated sand and gravel. They are dark-colored loam to cla}• loam in texture and generally are stratified. Thep are normally noncal- careous, but they are moderately influenced by soluble salts in Places. Thin lenses of sand, silt, or fine gravel may be m any of the layers. The soils of this land type absorb water at a moderate to slow rate, and the avatlable water capacity is high. Artificial drainage is ¢eneralh• needed to grow crops. Natural fertilit}• is high, but under the intensive man- agement used on these soils, artificial supplements are needed. Dfost of this land type is irrigated. In these areas, crops such as sugar beets, corn, small grains, and t-ege- tables can be grown. Alfalfa and irrigated pasture are well adapted. R'estern n•hentgrass, saltgrass, blue grams, and switch¢rass are grown in some areas. Loamy alluvial land, gravelly substratum Ilvl occurs es small areas in major drainagetcays. It is a principal source of grave]. Nearly al] areas nre subject to flooding from streams, and the floods often are damaging. The soils are shallow and s[rntified. The strata are of moderately coarse textured to moderate)}• fine tex- tured material that is underlain be river sand and gravel. In some places the soils are slightly influenced by soluble salts. The soils of this lend type absorb water at a rapid to slow rate. The available tcatrr rapacity is low, bat manl• areas have a high water table that is beneficial to plant growth. bfuch of this land type is cnltivatrd and irrigated. The principal crops are. truck crops adapted to the area, mainly velar}•, melons. sn-rrt corn. tomatoes. lethtce, carrots. onions, and cabbage. The best growing conditions can be maintained if the normal water tnblr is con- trolled so that it remains at n depth of 10 to ~0 inches below the surface during the growing season. nthrr ir- rigated crops include pasture mixturrs that require some irrigation but are parth• sustained by the water table in the gravel layers. Some of this land type is in native grass, mainly western wheatgrass, saltgrass, blue gramn, and stcitch- grnss. The wetter areas produce srdgcs, rushes, and cat- tails. This vegetation is largely sustained by the natural tenter table and by flooding. Little irrigation is needed. I-1 EXHIBIT I Sandy Alluvial Land Sandt• alhn•iel land (Sin) consists of an unstahle nccumn- lation of gravelly and sandy nllttt•ittm. It is in and adjacent to beds of intermittent streams throttehout the eastern three-fourths of Adams Connty. Duringg Periods of heavy ruin, the streambeds nre subject to flood- ing. and channels arc relocated and sediment is shifted and redeposited at slightly different locations. During dry spells, this land type is extremely droughty. Sandy alluvial land consists of mnrerial that was transported by water from the sand and gravel beds in or adjacent to the area. It is stratified becn»se of periodic flooding. Thin lenses or small pockets of silt. clay, and sand are also mixed with the gravel. This land type differs from Wet alluvial land pri- marily in that it is coarser textured thronghout and is oat affected by a water table. Sandy alluvial land is either barren or has only n sparse cover of weeds. It is used for grazing along with the better rangeland adjacent to it. Capability unit VIItc-1, nonirri~ated; not placed in n range site; tree planting suitability group 4. Rret Alluvial Land Wet alluvial ]end It/•/+) is on the nearly level bottom lands of the larger streams neat to stream chamtels throughout the county. The areas range from 20 to 150 acres in size. This land t}-pe is wet most of the time and is flooded by streamflow once to several times a year during periods of high water Included in mapping are small areas of Loam}- alluvial ]and, modcratel}• wet, a few small sand ettd gret-el bars. and areas underlain by heavy else, commonlc called oxbows. The matermis nre extremely variable in texture; they consist of stratified ]n}-ers of dark-colored silt, loam, and clap. The lavers arc generally less than 6 inches thick and are underlain b}- sand, fine sand, and some grace] at depths of 1 to 3 feet. The}• are wet at n depth of 2 feet most of the time and are common)}• wet to the surface throughout. the growing season. I~'atural fertility is moderate to good. Areas of this land type have a vegetative cover of water-tolerant plants, such as cattails end sedges, and are not. suitable for cnltication, because of the hazard of flooding from streams and a high water table. Under improved management, the production of native grass for grazing or hac is good. Generally a few cottonwood trees and willows arc present.