Stanislaus River Basin and Calaveras River Water Use Program
Threatened and Endangered Species Report - March 1995
Bay Delta and Special Water Projects Division, CA Dept. of Fish and Game
2.1 VALLEY REACH
The valley reach is that portion of the river from the confluence with the San Joaquin
River upstream to the Orange Blossom bridge (east of the city of Oakdale). It flows through
an area that is highly developed agriculturally and whose major crops are fruits and nuts. This
reach is approximately 47 river miles in length and has a gradient of 0.03 percent.
The major habitat type within this reach, valley foothill riparian, is primarily found
bordering the Stanislaus River. This habitat is characterized by a canopy layer of
cottonwoods, California sycamores, and valley oaks. Subcanopy cover trees are white alder,
boxelder, and Oregon ash. Typical understory shrub layer plants include wild grape, wild
rose, California blackberry, elderberry, button brush, and willows. The herbaceous layer
consists of sedges, rushes, grasses, miner's lettuce, poison-hemlock, and nettle.
Annual grassland is also a habitat type found within the valley reach of the river. This is
characterized as an open habitat dominated by annual grasses. Common species of annual
grassland habitats include wild oats, soft chess, ripgut brome, red brome, wild barley, and
foxtail fescue. Common forbs include redstem filaree, turkey mullein, clovers, and popcorn
flower.
Other habitat types within this reach are fresh emergent wetland, riverine, urban, and
disturbed. Fresh emergent wetland habitats are characterized by erect, rooted hydrophytes
such as sedge, nutsedge, rush, and cattail. The river comprised the riverine habitat; the cities
of Ripon, Escalon, Riverbank, and Oakdale comprised the category called urban. The
disturbed category identifies those areas showing disturbance in the forms of gravel mining,
rip-rapped stream banks, or similar man-made disturbances not suitable for inclusion with the
other categories used.
In some areas within this reach the riparian corridor is virtually nonexistent, primarily
due to farming which has encroached upon the riparian corridor practically to the river's edge.
In a few areas the riparian corridor is wide. One example of an existing wide riparian
corridor is in the Caswell Memorial State Park.
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