SU0001115 SSNL - Laserfiche WebLink

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DH- Delhi loamy sand, 0 to 2 percent slopes. This very deep, somewhat excessively drained soil is on nearly level dunes. It formed in wind modified alluvium from granitic rock sources. Elevation is 25 to 135 feet. The average annual precipitation is about 11 inches, the average annual air temperature is about 60 degrees F, and the average frost-free period is about 270 days. Typically, the surface layer is grayish brown and light brownish gray loamy sand about 16 inches thick. The upper 10 inches of the underlying material is grayish brown loamy sand. The lower part to a depth of 60 inches is pale brown sand. In some areas the surface layer is loamy fine sand or fine sand. _ Included in this unit are small areas of Honcut, Tinnin and Veritas soils on slightly lower positions. Also included are small areas of Delhi soils on 2 to 5 percent slopes on slightly higher positions. Included areas make up about 15 percent of the total acreage. Permeability of this Delhi soil is rapid. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow and the hazard of water erosion is slight. The water intake family for irrigation is 3.0. The hazard of soil blowing is severe. Most areas of this unit are used for irrigated cropland, orchards and vineyards. A few areas are used for homesite development. This unit is suited to irrigated row, field, orchard and vineyard crops. The main limitation is low available water capacity. General management considerations include the severe hazard of soil blowing. The high percentage of sand in this soil reduces the amount of moisture available for plant growth. Because this soil is droughty, applications of irrigation water should be light and frequent. Water should be applied in amounts sufficient to wet the root zone but in amounts small enough to minimize the leaching of plant nutrients. Sprinkler and drip irrigation systems are suited to this - unit. Use of this method permits the even, controlled application of water, reduces runoff and minimizes the risk of erosion. A tillage pan forms easily if this soil is tilled when wet. Chiseling or subsoiling breaks up the tillage pan. When the wind velocity is high in spring, soil blowing can be reduced by using all crop residue and practicing minimum tillage. If this unit is used for homesite development, the main limitation is rapid permeability in the substratum. Community sewage systems may be needed to prevent contamination of water supplies as a result of seepage from on-site sewage disposal systems. The map unit is in capability units IIIs-4 (MLRA-17), irrigated and IVe-4 (MLRA-17), nonirrigated. This map unit is vegetative soil group B. SAN JOAQUIN COUNTY SOIL SURVEY PRELIMINARY DRAFT 7/90 SUBJECT TO CHANGE