2002-06-18_PERMIT FILE - M2002062

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Official Series Description - ROCKY_FORD Series LOCATION ROCKY FORD CO Established Series Rev. A7C 02/97 ROCKY FORD SERIES Page 1 of 2 Typically, Rocky Ford soils have grayish brown very calcareous clay loam manmade Ap horizons and pale brown calcareous loam C horizons. TAXONOMIC CLASS: Fine-silty, mixed, calcareous, mesic Ustic Tortiorthents TYPICAL PEDON: Rocky Ford clay loam -cultivated (Colors aze for dry soil unless otherwise noted.) AP--O to 12 inches; grayish brown (slightly darker than lOYR 5/2) clay loam, dark grayish brown (slightly dazker than l OYR 4/2) moist; weak coarse subangulaz blocky structure that parts to fine and very fine granules; slightly hard, very friable, slightly sticky, slightly plastic; primary peds aze hard, firm; moderate amounts of undecomposed and partially decomposed organic materials; calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (10 to 20 inches thick) Cca--12 to 60 inches; pale brown (lOYR 6/3) loam, brown (lOYR 5/3) moist; massive; hard, friable, slightly sticky, slightly plastic; visible secondary calcium cazbonate occurring mostly as small concretions or in seams and streaks throughout the horizon; calcareous; moderately alkaline (pH 8.2). TYPE LOCATION: Prowers County, Colorado; .3 mile north and 100 feet east of W 1/4 corner Sec. 33, T. 22 S., R. 45 W. RANGE IN CHARACTERISTICS: These soils are usually calcareous throughout, but are leached to depths of 2 or 3 inches in some pedons. Gypsum content of a majority of subhorizons in the control section ranges from 0 to 1.5 percent by weight. Exchangeable sodium ranges from 0 to 14 percent in a majority of subhorizons of the control section and there is no subhorizon as much as 3 inches thick above a depth of 20 inches that exceeds 15 percent. Conductivity ranges from 0 to 14 millimhos in most subhorizons of the control section and there is no subhorizon as much as 3 inches thick above a depth of 20 inches that exceeds 14 millimhos. Continuous subhorizons of genetically concentrated visible secondary calcium carbonate and/or sulfate do not occur above a depth of 40 inches although some visible calcium carbonate and/or sulfate occurs inconsistently at any depth or occurs uniformly throughout the profile as a natural feature of the parent material. The control section is usually loam, clay loam, silt loam or silty clay loam but clay ranges from 18 to 35 percent, silt from 20 to 60 percent, and sand from 10 to 60 percent with less than 15 percent being fine or coarser sand. Rock fragments range from 0 to 5 percent and are mainly 1/2 to LO inches in diameter. Subhorizons redder than 7.SYR occur in a few pedons but the major part of the control section above a depth of 40 inches has hue of 7.SYR or yellower. Manmade Ap horizons ranging from 10 to 20 inches thick that are medium to moderately fine textured, that border mollic http://wwwstatlab.iastate.edu/cgi-bin/osd/osdname.cgi?-P 3!15/2002