Laserfiche WebLink
Chemical Pronerties and Natural Fertilirv -Normally there are no serious chemical limitations to the use <br />• of the soils of mapping unit number 1. N'hilc most of the components arc calcareous throughout, calcium <br />carhonate does not occur in concentrations high enough to seriously affect nutrient availability. <br />All of the soils of mapping unit number 1 have lower than normal natural fertility levels of the general <br />area. Nitrogen and phosphorus are low even in the A horizons and available supplies decrease with depth. <br />Potassium is not known to be deficient, nor arc there any known deLciencies in trace elements. <br />The soils of this mapping unit are poorly weathered soils and have little or no natural reserve of plant <br />nutrients. ]n consequence, they are unable to regenerate adequate levels of fertility alter disturbance. <br />Disturbed areas in which revegetation is to be attempted should have a supplemental fertilizer program. <br />~1annine Unit Number 4 - Moderately deep (20 to 40 inches to bedrock) and deep (more than 40 inches <br />to hedrock) light colored, medium to moderately fine textured (18 percent to 35 percent clay) undeveloped <br />sulk having no soil horizonation other than a slightly darkened surface horizon and weak and inconsistent <br />horizons of secondary carbonate accumulation (Torriorthents) or weakly developed soils having slightly <br />darkened surface horizons, brighter colored subsurface horizons of weak to moderate structure and weak <br />horizons o(secondary carbonate accumulation (Camborthids) occurring in parts of the study area where <br />the mean summer soil temperature (June, July, and August averages measured at 20 inches) is 59°F or <br />warmer. <br />Classification of Maior Components - The components ]fisted below comprise the major pan of the <br />mapping unit: <br />A. Ustic Torriorthents (Regosols of semi-arid regions). <br />I. Fine-loamy, mixed, (calcareous), mesic Tamil}•. <br />(Thcdalund Scrics) <br />(Kim Scrics) <br />(Shavano Series) <br />2. Fine-loamy, mixed, (calcareous), frigid family'. <br />(Patent Series) <br />B. Ustollic Camborthids (Regosols of Semi-arid regions). <br />1. Fine-loamy, mixed, mesic. <br />(Zicivicd Scrics) <br />C. Borollic Camborthids (Regosols of cold dry regions). <br />1. Fine-loamy, mixed. <br />(Chapperton Series) <br />Extent and Maior Areas of Occurrence -Mapping unit number 4 occurs in limited acreage in the study <br />area. Largest areas are located on the vallcv filling sidesiopes east and north of 1`linnesota Creek and its <br />eastern fork in the southwestern part of the stud}' area. <br />Characteristic Tono^ranhv -These soils occur on gently to moderately sloping vallcv filling sideslopes <br />and coalescing alluvial fans below steep escarpment-like areas bordering the major stream valleys. They <br />h:rvc been dissected by numerous steep walled drainage channels that formed more or less at right angles <br />to the major channel of the North Fork of the Gunnison River. <br />These areas arc young land surfaces that are still geologically active. Slopes range from about 5 percent to <br />40 percent with the steeper sloping areas normally occurring along the edges of the dissecting streams. <br />• Physical Pronerties - The soils of this unit are young and lack well developed natural soil structure. They <br />typically have moderate grades of soil structure, making management a requisite in an operation requiring <br />