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Pagel. (and ;1. 515) - Foothill Woodland The author describes 3 kinds of foothill oak woodland: savannah, the closed canopy Brovelli Woods, and riparian woodland. The savannah that the author describes is better characterized as a valley D67 oak woodland sensu Holland (1986). This plant association is found primarily on the north central portion of the property. Within the predominately valley oak (Ouercugt labata community are found scattered Individuals of interior live oak Quem us wislize , blue oak (Qum douglasii , coastal live oak (Quercus agdfofla) and California buckeye (qua caljfQUUca). The author failed to notice the poor health of many of these trees, evidently the result of drought and the indirect Impacts from grazing such as soil compaction. The Biotics Study is confusing about the status of the community type in the closed canopy Brovelli Woods. Both the terms foothill woodland and riparian are used. K was correctly pointed out that interior live oak predominates valley oak by a 4:1 ratio, with fewer Individuals of ash (Fraxinus jam, elderberry (Sambucus meq$), cottonwood (Populus frgMont11), and willows (Saa spp.). The understory Is dominated by poison oak (Toxicodendron diversilobum), sedge (Carex fie, blackberry (Rubusprocerus,g. urcinatus , and California grape Qdtla califomicus). The vegetation of the Brovelli Woods does not conform to the classic riparian community type. Under pristine conditions, the classic valley riparian forests are formed by meandering streams and rivers having unconfined, low in elevation banks. During periods of flooding, erosion (degradation) occurs on the Dss outside banks, and deposition of sediments (aggradation) occurs on the inside banks and on the adjacent, low floodplains. As flood waters recede, willows, cottonwoods, ash, boxelder (Am a$gWadp , and valley oaks regenerate on the adjacent floodplains away from the river's edge. The Brovelli Woods do not fit this classic pattern of riparian vegetation. The reason for this is that the banks of the Mokelumne River, In comparison to classic meandering valley streams (e.g., the Cosumnes River), are relatively high In elevation thus serving to confine the river's course. As a consequence, the vegetation at this site is found on a relatively stable landform not subject to river meandering. Being higher in elevation, the site Is comparatively dry. Even In pre- dam conditions, the Mokelumne River at this location would not have flooded as extensively as would other rivers such as the Cosumnes. This explains why the woods consist predominately of interior live oak, a comparatively upland species, with fewer numbers of valley oak. Only a few scattered riparian species, such as willows, cottonwoods, and ash are found In moist depressions. The Brovelli Woods therefore approximates a foothill interior live oak woodland sensu Holland (1986) and is not a riparian kind of vegetation. The reason that these comments are Important to note Is that the Brovelli Woods are lacking in several key structural components of riparian forests such as trees of the intermediate size -- ash and boxekier-- and additionally in having a poor representation of willows and cottonwoods. This comparative lack of plant height, structure, and diversity results in less bird diversity compared to true riparian systems. 3 VI-83