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slopes lying along the banks of the Mokelumne River and along the northeast portion of the southernmost
<br /> and largest lakebed. Topographic features on the property are commonly associated with vegetation
<br /> patterns.
<br /> Oak-buckeye savanna and annual grasslands comprise the majority of the property. The oak forest is the
<br /> last remaining example of this plant community that exists in this part of California. The lakes are
<br /> surrounded by oaks,cottonwoods,elder,buttonbrush and willow. Along the river are riparian woodlands
<br /> of cottonwood,willows,buttonbrush,and oak. Oak species include interior live oak(Quercus wislizenii),
<br /> valley oak(Q. lobata),and blue oak(Q. douglasii),with interior live oak being the dominant forest tree.
<br /> Buckeye (Aesculus californiaca)grows both singly and in clusters on the property. Prior to the draining
<br /> of the sloughs, marshland vegetation including grasses, tules, and cattails grew on the valley floor.
<br /> Stands of poison oak, blackberry, wild grape and wild rose are present in the wooded areas.
<br /> Native perennial grasslands have been replaced by Mediterranean annual grasses grown for cattle grazing.
<br /> Some of the introduced species include ripgut brome (Bromus rigidus), wild oats (Avera fatua), and
<br /> foxtail (Hordeum leporinum). Small areas of native perennial grasses, such as saltgrass (Distichlis
<br /> spicata)and creeping wildrye(Leymus triticoides) still exist on the property. Most of the unique vernal
<br /> pool vegetation has been depleted by cultivation and grazing disturbances.
<br /> This area of the Central Valley historically supported abundant animal species, such as the tule elk,wolf,
<br /> coyote,kit fox,rabbit,badger,mink,weasel, beaver,river otter,skunk,ground squirrel, and other small
<br /> mammals. The Tracy Lakes and Mokelumne River supported river mussels and trout, sculpin, salmon,
<br /> sturgeon, squawfish, perch, suckers, smelt and flounder. Waterfowl was another important resource;
<br /> species included geese, ducks,swans, eagles,brants,pelicans, ibis,herons,cranes and cormorants. The
<br /> property currently supports eight species of mammals, 47 species of birds, two species of reptiles, and
<br /> two species of amphibians and eight species of fish (Management Plan, 1991; McGinnis, 1991).
<br /> The property's distinct soil type, San Joaquin Sandy Loam, is a a river bank formation of glacial, fluvial
<br /> deposits. Large areas west of the property have been stripped away, leaving only a bevelled end of this
<br /> deposit on site (McElhiney, 1991). Another primary soil type in the project area is Columbia Fine Sandy
<br /> Loam, a very deep, poorly drained soil that lies on nearly level flood plains and is formed in alluvium
<br /> from mixed rock sources. Bruella Sandy Loam, also found on site, is another deep, well drained soil
<br /> that is found on nearly level low terraces. It is formed in alluvium from granitic rock sources, and has
<br /> a moderately slow permeability. Other soil types found on the property include Kimball Loam and
<br /> Xerofluvent.
<br /> Climate in the area is typified by a Mediterranean pattern of short winter rains and long summer
<br /> droughts. The mean winter temperature is 45T, and the mean summer temperature is 75°F, often
<br /> exceeding 90T during the daytime. The Lodi weather station receives approximately 16 inches of
<br /> precipitation annually (Management Plan, 1991). The region is also typified by thick, low-lying fog
<br /> known as "tule fog," which occurs often in the winter, on an average of 43 days per year.
<br /> The San Joaquin Valley was an ideal habitat for early Native Americans. The primary commodities
<br /> needed that were lacking were rocks and minerals, and these deficiencies were alleviated through trade
<br /> and by substituting baked clay for stone. Abundant game and vegetation,plus a mild climate, supported
<br /> a large prehistoric population. The population of San Joaquin Valley, including of the Plains Miwok and
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