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ran Joaquin County, California 113
<br /> r.Froper stocking rates, pasture rotation, and restricted by the hardpan at a depth of 20 to 40 inches. Roots are
<br /> ,azing during wet periods help to keep the pasture in restricted to cracks and the faces of Peds in the
<br /> ,,aod condi ion and protect the soil from compaction. claypan, which is at a depth of 10 to 20 inches. Water
<br /> If this unit is used for homesite development, the is briefly perched above the claypan and hardpan after
<br /> (F—Iain limitations are the moderately slow permeability periods of heavy rainfall or irrigation. Runoff is ponded
<br /> ;id low str ngth. The occasional flooding is a hazard. in the small vernal pools, is very slow or ponded in
<br /> On sites fob septic tank absorption fields, the leveled areas, and is slow on the convex slopes. The
<br /> oderately slow permeability can be overcome by hazard of water erosion is slight. The rate of water
<br /> creasing the size of the absorption field. Properly intake in irrigated areas is 1.5 inches per hour.
<br /> esi nin buildings and roads can offset the limited Most areas are used for livestock grazing r
<br /> a g g 9 ga go for
<br /> cid,lonsite
<br /> bility of th soil to support a load. Dikes and channels irrigated pasture, irrigated crops, or vineyards. A few
<br /> athave o tlets for floodwater can protect buildings areas are used for dryland grain crops or homesite
<br /> sewage disposal systems from flooding. development. This unit may provide wetland functions
<br /> .""This ma unit is in capability units IIw-2 (MCRA-17), and values. These should be considered in plans for
<br /> ,gated, arid iVw-2 (MLRA-17), nonirrigated. It is in enhancement of wildlife habitat or land use conversion.
<br /> age#a#ive oil group A. Where this unit is used for livestock grazing, general
<br /> management considerations include saturated soil
<br /> X235=-Sa Joaquin sandy loam, 0 to 2 percent conditions in concave areas following rainy periods. The
<br /> lopes:•Thi moderately well drained, nearly level sail is characteristic plant community is mainly soft chess,
<br /> P.vn It is moderately deep to a hardpan. It ripgut brome, foxtail fescue, and filaree. Grazing should
<br /> termed in alluvium derived from granitic rock sources. be delayed until the soil is firm enough to withstand
<br /> Nd's"c'a'iterad
<br /> e-rlative egetation is mainly annual grasses, forbs, trampling by livestock and the more desirable forage
<br /> California white oak. Slopes are complex, plants Have had an opportunity to set seed.
<br /> S and.the
<br /> landscape is characterized by hummocky This unit is suited to irrigated pasture. The main
<br /> icroreiief, depressions, minor drainageways, and limitations are the complex slopes and the very low
<br /> reas,ttat have been.leveled. Meandering available water capacity. Leveling helps to ensure a
<br /> arainagew ys and closed depressions fill with water to uniform application of water. Because the soil is
<br />} forin; vernaI pools during the winter in many areas, droughty, the applications should be light and frequent.
<br /> aevatidn.
<br /> JE 20 to 150 feet. The average annual The water can be applied by sprinkler and border
<br /> recipitatio 'is about 14 inches, the average annual air methods. Proper stocking rates, pasture rotation, and
<br /> I _03is about 61 degrees F, and the average restricted grazing during wet periods help to keep the
<br /> est free p rind is.about 275 days. pasture in good condition and protect the soil from
<br />' TypEca!! the surface layer is brown sandy loam compaction.
<br /> about i3 in hes`thick. The upper part of the subsoil is a This unit is suited to irrigated row, field, and vineyard
<br /> ��aYPan of, rown`clay about 7 inches thick. The lower crops. The main limitations are the complex slopes, -
<br /> �artto a tl, ptl of 60 inches is a brown and tight brown, depth to the very slowly permeable claypan and
<br /> tdurated ardparn. In some areas the surface layer is hardpan, and the ver low available
<br /> Y p y e water capacity.
<br /> fi0.ne sandy'oam loam, or gravelly sandy loam. Leveling helps to ensure a uniform application of water.
<br /> On fuded �n thjs">Jnit are small areas of Bruella and Because of the restricted permeability, the applications
<br /> 3°Wnasoi s on the slightly higher terraces, Jahant soils should be regulated so that the water does not stand on
<br /> .,Vandsca e
<br /> Qac ,, positions similar to those of the San the surface and damage the crops. The hardpan limits
<br /> quip so 1, and .Madera soils on the slightly higher the suitability for deep-rooted crops. Where feasible,
<br /> !artsof tfti' landscape:Also included are small areas of deep ripping of this restrictive layer can help to
<br /> Y^LTJ
<br /> Je I"aus; that have slopes of 2 to 5 percent overcome this limitation. A tillage pan forms easily if the
<br /> °�5ae orti the sli htl hi arts of the landscape, soil is tilled when wet. Chiseling or subsoiling breaks up
<br /> 9 y higher p
<br /> awe as much.as 20 inches of overburden, the pan. Because the soil is droughty, applications of
<br /> ire most of the soil horizons have been irrigation water should be light and frequent. Furrow,
<br /> altered orfragments of hardpan and border, and sprinkler irrigation systems are suitable.
<br /> xlaisvare within 10 inches of the surface as Returning crop residue to the soil or regularly adding
<br /> d leveling Included areas make up about other organic material improves fertility, minimizes
<br /> ttotal acreage. crusting, and maintains the rate of water intake.
<br /> z=�eT
<br /> °so w in the San Joaquin soil. Where this unit is used for dryland grain crops, the
<br /> 'opacity is. very low. The shrink-swell main limitation is low rainfall during the growing season. j
<br /> aThe effective rooting depth is limited Because the amount of precipitation is not sufficient for
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