1988-04-29_PERMIT FILE - C1981008A (47)

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34 Established Series Rev. AJC 4/73 SHAVANO SERIFS The Shavano series is a member of the fine-loamy, mixed (calcareous), mesic family of Ustic T'orriorthents. Typically, Shavano soils have light brown, very friable, granular, calcareous A horizons, and very pale brown, calcareous, fine sandy clay loam C horizons, over hard calcareous sandstone at a depth of 26 inches. Typifying Pedon: Shavano fine sandy clay loam - grassland (Colors are for dry soil unless otherwise noted.) Al 0-4"--l.ight brown (7.5YR 6/3) fine sandy clay loam, brown (7.5YR 5/3) moist; moderate fine granular structure; soft, very friable, slightly sticky, slightly plastic; calcareous; moderately alkaline (pli 8.0); clear smooth boundary. (3 to 8 inches thick) AC 4-7"--Very pale brown (IOYR 7/3) fine sandy clay loam, light yellowish brown (IOYR 6/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky, slightly plastic; calcareous; moderately alkaline (pH 8.0); gradual smooth boundary. (0 to 5 inches thick) Cca 7-2b"--Very pale brown (IOYR 7/3) fine sandy clay loam, light yellowish brown (10YR 6/4) moist; massive; hard, firm, slightly sticky, slightly plastic; 10 percent flat sandstone fragments in the lower 10 inches; some visible secondary calcium carbonate occurring as concretions; calcareous; moderately alkaline (pil 8.2); abrupt wavy boundary. (7 to 17 inches thick) R 26-40"--hard calcareous sandstone. Type Location: Montrose County, Colorado; approximately 350 feet east of N14 corner sec. 3, T.48N., R.10W. Range 1n Characteristics: Depth to uniformly calcareous material ranges from 0 to 10 inches. Depth to the lithic contact ranges from 20 to 40 inches. 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 15 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 15 inches that exceeds 15 percent. Conductivity ranges frum 0 to 14 millimhos in must subhorizons of the control section and no subhoriton as much as 3 inches thick above 15 inches exceeds 14 millimhos. Continuous subhorizons of genetically concentrated visible secondary calcium carbonate and/or sulfate does not occur in the control section although some visible calcium carbonate and/or sulfate occurs inconsistently at any depth or occur uniformly throughout the profile as a natural feature of the parent material. The control section is usually heavy sandy loam or sandy clay loam, but clay ranges from 18 to 35 percent, silt from 5 to 30 percent, and nand from 40 to 75 percent with more than 35 percent being fine or coarser sand. Rork fragments range from 0 to 15 percent and are mainly 1/2 to 10 inches in diameter. Subhorizons redder than 7.5YR occur in some pedons but a major part of the control section above the bedrock has hue of 7.5YR or yellower. The A horizon has hue of 5Y through 7.5YR, value of 5 through 8 dry, 3 through 7 moist, and chroma of 1 through 4. It ranges from mildly alkaline to strongly alkaline (1:5 dilution unbuffered organic dye). The C horizon normally has hue of 5Y through 7.5YR, but subhorizons redder than 7.5YR occur in some pedons. It is moderately or strongly alkaline 0:5 dilution unbuffered organic dye). Calcium carbonate equivalent of the fine earth ranges from less than 1 to about 10 percent, but visible carbonate is not concentrated in genetic horizons. Competing Series and their Differentiae: These are the El Rancho, Kim, Neville, Pojoaque, Sixmile, and Thedalund series. All of these suits lack lithic contacts at a depth of 40 inches or less. f.l Rancho, Neville, and Pojoaque soils have hue of 5YR or redder in a majority of subhorizons. Kim. Sixmile and Thedalund soils have less than 35 percent fine or coarser sand. Sett-ice: The Shavano soils are on gently to steeply sloping hills, ridges, and mesa tops. Slopes typically range from about 2 to 40 percent or more, the soils formed in moderately thin, calcareous, medium to moderately fine textured materials weathered from sandstone and sandy shale. At the type location the mean annual precipitation is about 10 inches with peak periods of precipitation occurring in the spring and early summer months. Mean annual temperature is 48°F, and mean summer temperature is 69°F. Principal Associated Soils: These are the Lazear soils and the competing Thedalund soils. Lazear soils have bedrock at depths of 10 to 20 inches.