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APPENDIX I - BIOLOGICAL RESOURCES Figure 4.7-3 shows the disturbed areas within the forest stand, and Figure 4.7-4(A)(B)shows the disked areas from within and along the edge of the western edge of this stand. Because of the closed canopy nature of the woodland,the understory away from the river edge is quite sparse and open(Figure 4.7-5). 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 the recently logged stumps that have been pulled out and deposited in piles near the forest edge (Figure 4.7- 2(A)). This large range of tree age, along with a good crop of oak seedlings, indicates that this forest has been functioning in a normal ecological manner up to the recent disturbance. Of special significance is that some forest segments away from the golf course construction area 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, occurring within the broader foothill woodland plant community (Munz, 1965). In addition to the trees of the foothill woodland proper, it contains Fremont cottonwood (Populus fremonti), 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) (Figure 4.7-6(A)(B)). In many river edge areas the wild grape forms massive lianas (vines) which completely cover some of the small and medium size trees (Figure 4.7-6(B)). It is this extensive grape vine growth with its swinging vines that imparts a jungle-like appearance to this classic remnant of valley riparian woodland. Only the preserved mature riparian woodland segments found in the Consumnes Preserve and Caswell State Park equal that present along the Mokelumne River in Brovelli Woods. Valley Grassland The non-wooded areas of the project site originally supported a complex of bunch grass species. After a century of heavy grazing,however,these have been replaced by a wide variety of introduced grass and forb species such as wild oat (Avera fatua), Italian rye (Lolium multiflorum), ripgut brome (Bromus mollis), filaree (Erodium malacoides), wild mustard (Brassica sp.) and wild radish (Raphanus sp). Presently grazing pressure appears only moderate, and in some areas a relatively thick grass mat has formed, which in turn promotes many grassland rodent species (Figure 4.7-1). 7