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Water is briefly perched above the claypan and hardpan after periods of heavy rainfall or irrigation. The rate of water intake in irrigated areas is 1.5 inches per hour. Soil type#195': This is approximately 60%of the soil at the site. Name: Madera-Alamo complex, leveled,0 to 1 percent slope. -- This soil is 65%Madera sandy loam and 20%an Alamo soil that has overburden of sandy loam. The Alamo soil was originally in old drainageways prior to leveling. Included in unit are small areas of Jahant and San Joaquin soils that have been ripped or leveled and have remnants of claypan and hardpan materials through out the profile. The Madera soil is moderately deep to a hardpan and is moderately well drained It is formed in alluvium derived from granitic rock sources. Typically,the surface layer is grayish brown sandy loam about 10 inches thick. The upper part of the subsoil is brown clay about 10 inches thick The lower part to a depth of 60 inches is a brown and pale brown, indurated, silica-cemented hardpan. In some areas the surface layer is fine sandy loam or loam. Permeability is very slow in the Madera soil. Available water capacity is low. The shrink-swell potential is high. The effective rooting depth is limited to the hardpan at a depth of 20 to 40 inches. Roots are restricted to cracks and the faces of peels in the claypan, which is at a depth of 10 to 25 inches. Water briefly perched above the claypan and hardpan after periods of heavy rainfall or irrigation. Runoff is very slow and the hazard of water erosion is slight. The rate of water intake in irrigated areas is 1.5 inched per hour. The soil is subject to rare flooding, which occurs during years of abnormally high precipitation. The Alamo soil is moderately deep to a hardpan and is poorly drained. It formed in alluvium derived from mixed rock sources. Typically the surface layer is gray and brown sandy loam overburden derived from the adjacent Madera soil. It is about 12 inched thick. Below this is a buried surface layer of dark gray and dark grayish brown clay about 13 inches thick The upper part of the subsoil is dark gray clay about 9 inches thick The lower part to a depth of 60 inches is a brown and pale brown, indurated, silica-cemented hardpan. In some areas the surface layer is loam or clay loam. Permeability is very slow in the Alamo soil. Available water capacity is low. The shrink-swell potential is high. The effective rooting depth is limited by the hardpan at a depth of 20to 40 inches. Roots are restricted to cracks and the faces of pods in the buried soul, which is at a depth of 12 to 20 inches. Water is perched within a depth of 12 inches after periods of heavy rainfall or irrigation. Runoff is very slow and water erosion is slight. The rate of water intake in irrigated areas is 1.5 inches per hour. The soil is subject to rare flooding, which occurs during years of abnormally high precipitation. The main limitation is the low available water capacity. Because these soils are droughty, applications of irrigation water should be light and frequent. A drainage system may be needed Irrigation water may be applied by sprinkler and border methods. The hardpan limits the suitability for deep-rooted crops. Returning crop residue to the soils or regularly adding other organic material improves fertility, minimizes crusting,and maintains the rate of water intake. On site for septic tank absorption fields must be increased in size to compensate for very slow permeability. This map unit is in capability unit Ivs-3, irrigated and non-irrigated. The Madera soil is in vegetative soil group D,and the Alamo soil is in vegetative soil group E. Soil type#182': This soil is approximately 15%of the soil at the site. Name: Jahant loam,0 to 2 percent slopes. This well drained, nearly level soil is on low terraces. It is deep to a hardpan. It formed in alluvium derived from mixed rock sources. A few areas are dissected by intermittent soughs that have been filled as a result of land leveling. Typically, the upper part of the surface layer is grayish brown loam about 5 inches thick. The lower part of the surface layer and the upper part of the subsoil are dominantly pale grown and dark brown loam about 26 inches thick The next 18 inches of the subsoil is a claypan of brown and dark brown clay loam and clay. The next 4 inches is a brown and dark brown, strongly cemented hardpan. The lower part of the subsoil to a depth of 60 inches is a light grown and brown, indurated hardpan. In some antis the surface layer is fine sandy loam or sandy loam. "Soil Su ev Of San Joaquin Couiay.CA 1992 Western Design/David Avila 2000 10