Riparian
forest and shrub communities: William Brewer noted in his 1864
trip through Owens Valley, "The eastern slope of the Sierra
is almost destitute of trees save in the canyons and along the streams."
(Farquhar 1974) This may be the first written reference to
Owens Valley wooded riparian communities. These occur, as
Brewer noted, along streams flowing from the Sierra Nevada,
along the Owens River, and in other areas of very high water tables.
Important tree species include Populus fremontii (Fremont
cottonwood), Salix
gooddingii (Gooddings black willow), Salix laevigata
(red willow) and, along a few streams in southern Owens Valley,
Quercus kelloggii (black oak).
Common shrubs include Salix exigua (Coyote willow),
Betula occidentalis (water birch) and Rosa woodsii
(wood rose). Leymus
triticoides (beardless wildrye) is a common grass and rushes
and sedges are abundant as well.
Tamarix ramosissima (tamarisk, or salt cedar) a non-native
shrubby tree has invaded many riparian areas in the Owens Valley
and is the object of on-going eradication efforts.
Riparian forest communities statewide are classified
as very threatened by the California Natural Diversity
Database (Sawyer and Keeler-Wolf 1995).
Under
the EIR to the LTWA stands of vegetation of "significant environmental
value" such as "riparian vegetation dependent on springs
and flowing wells, stands of willows and cottonwoods" not already
shown on management maps were to be identified by the Technical
Group for monitoring purposes (p. 5-5 City of Los Angeles Department
of Water and Power and County of Inyo 1990). As of February
2004, I know of nothing to indicate the Technical Group has ever
identified these stands nor initiated the required monitoring.
The
extensive riparian woodland which formerly existed along the Owens
River has been greatly diminished due to Los Angeles's de-watering
of the River south of the aqueduct intake at Aberdeen.
The Lower Owens River Project (LORP) which calls for restoration
of 40 cfs flows in the River from the aqueduct intake down to a
site near Lone Pine (close to the bed of Owens Lake) is expected
to help riparian forest and shrub communities along the approximately
60 miles of river channel to be re-watered.
Literature
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