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4.7 BIOLOGICAL RESOURCES Plant Communities Foothill Woodland A foothill woodland community dominates the project site and exists in three different forms. The most extensive of these is an oak savanna association composed primarily of interior live oak (Quercus wislizenii) and valley oak (Quercus lobata)with smaller numbers of coast live oak (Quercus agrifolia) and blue oak (Quercus douglasii)scattered throughout(Figure 4.7-1). This savanna association is also somewhat unusual in that it contains relatively large numbers of California buckeye(Aesculus califomica) which occur both singly and in small clusters. Tree density in the savanna association is quite variable, ranging from only a few trees per acre up to as many as 20 or more mature specimens per acre plot (Figures 4.7-9). The most spectacular segment of the foothill woodland community occurs in the form of a closed canopy forest known locally as Brovelli Woods. This excellent example of a foothill/riparian woodland stand remained essentially untouched until 1989 when approximately 12 per cent of the total 90 acre stand was cleared in the initial preparation of the proposed golf course. Figure 4.7-10 shows the inroads into the forest stand that the clearing project produced. Twenty to 30 years previously, approximately 10 acres of the forest had been cleared for farming purposes (Brovelli, 1989). This previously cleared area is currently being restored by the applicant. Interior live oak numbers exceed those of valley oak in approximately a 4:1 ratio, with occasional specimens of box elder(Acer negundo),Oregon ash(Fraxinus oregona),and California buckeye scattered throughout. The forest contains trees in many age categories, with some of the older specimens averaging well above 100 years. The later estimates were obtained from annular ring counts from stumps that have been pulled out and deposited in piles near the forest edge. This large range of tree age along with a good crop of oak seedlings indicates that this forest has been functioning in a normally ecological manner. Of special significance is that some forest segments away from the golf course construction area still contain dead and dying trees which contribute greatly to the overall worth of this site as a viable wildlife habitat. Thus, Brovelli Woods appears to have entered an early stage of "old forest" age, thereby providing far more nesting, denning, and feeding opportunities for wildlife than could an early or middle-aged woodland. The third segment of the woodland habitat can best be defined as riparian woodland occurring within the broader foothill woodland plant community as described by Munz, 1965. In addition to the trees of the foothill woodland proper it contains Fremont cottonwood (Populus fremondi), willow (Salix sp.), and shrubs, such as elderberry (Sambucus sp.), wild rose (Rosa californica), poison oak (Rhus toxicodendron),blackberry (Rubus sp.), and wild grape (Vitis california) (Figures 4.7-7& 4.7-10). In many river edge areas the wild grape forms massive lianas which completely cover some of the small and medium size trees. It is this extensive grape vine growth with its "Tarzan swing" vines that imparts 4.7-9