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Permeability is moderate in the Manteca soil. Available water capacity is low. The effective rooting depth is limited by the hardpan at a depth of 20 to 40 inches. Depth to the water table is more than 6 feet, but water may be perched above the hardpan after periods of heavy rainfall or irrigation. Runoff is slow, and the hazard of water erosion is slight. The rate of water intake in irrigated areas is 1.5 inches per hour. The hazard of soil blowing is moderate. The soil is subject to rare flooding, which occurs during years of abnormally high precipitation. Most areas are used for irrigated crops or vineyards. A few areas-are used as irrigated pasture or for homesite development. This unit may provide wetland functions and values. These should be considered in plans for enhancement of wildlife habitat or land use conversion. This unit is suited to irrigated row, field, and vineyard crops. The main limitations are depth to the hardpan and the low available water capacity. General management considerations include the hazard of soil blowing. The hardpan limits the suitability for deep-rooted crops. Where feasible, deep ripping of this restrictive layer can help to overcome this limitation. Because the soil is droughty, applications of irrigation water should be light and frequent. Careful + applications are needed to prevent the buildup of a high water table. Furrow, border, and sprinkler irrigation systems are suitable. A tillage pan forms easily if the soil is tilled when wet. Chiseling or subsoiling breaks up the pan. When the wind velocity is high in spring, the hazard of soil blowing can be reduced by properly managing all crop residue and by minimizing tillage. k f This unit, is suited to irrigated pasture. Irrigation water can be applied by sprinkler and border t ' methods. Leveling helps to ensure a uniform application of water. Proper stocking rates, pasture rotation, and restricted grazing during wet periods help to keep the pasture in good condition and protect the soil from compaction. If this unit is used for homes'ite development, the main limitation is depth to the hardpan. The rare flooding is a hazard. Ripping the hardpan improves permeabiRy and thus also improves the suitability of the soil for septic tank absorption fields. Houses, roads, and streets should be constructed above expected flood levels. This map unit is in capability units Ills-8 (MLRA-17), irrigated, and IVs-8 (MLRA-17), nonirrigated. It is in vegetative soil group G. 250-Stockton clan 0 to 2 percent slopes. This somewhat poorly drained, nearly level soil is in basins It is deep to a hardpan. It formed in alluvium derived from mixed rock sources. Mottles in the profile indicate a somewhat poorly drained soil; however, drainage has been improved by levees and reclamation projects A few areas are dissected by intermittent sloughs that have been filled as a result of land leveling. Elevation is sea level to 100 feet. The average annual precipitation is about 14 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 dark gray clay about 29 inches thick. The upper 8 inches of the subsoil also is dark gray clay. The next 5 inches is light brownish gray; and grayish brown clay loam. The lower part to a depth of 60 inches is a variegated dark grayish brown and •dark brown, weakly cemented to strongly cemented hardpan. In some areas the surface layer is silty clay, silty t.: clay loam, or clay loam. Included in this unit are small areas of Archerdale and Vignolo soils on the slightly higher parts of the landscape; Galt and Jacktone soils in landscape positions similar to those of the Stockton soil;