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Ecological Evaluation of Brovelli Woods P.C. Muick Despite at least forty years of cattle grazing, a number of healthy-sapling sized blue and valley oaks were observed in the savanna area, generally at lower elevations closer to the lake beds . Few sapling-sized oaks or buckeyes were noticed on higher ground away from the lake bed. It is probable some regeneration has taken place during the period of cattle grazing and is likely to continue or increase with reduction of grazing. I found no shrubs mixed in among the trees in the savanna although it is likely they occurred in the past. The herbaceous species consist primarily of introduced exotic species, typically associated with a livestock operation , and native annuals and perennials. I found no native , perennial grasses in my cursory walk through the grassland . With reduction or cessation of grazing , a few shrub species may recolonize the savanna areas. Without a nearby seed source it is unlikely that native perennial grasses will recolonize the savanna . A preliminary list of the herbs and grasses found in the savanna is included in Appendix 3 Section 1 . Vernal Pools Hog wallows, a term used for the microrelief associated with vernal pools vegetation , are commonly associated with the San Joaquin soil type . Several vernal pools, with a combined total estimated area of twp acres , were observed and mapped on the eastern third of the property. Dr. Tom Griggs identified several species during a visit to the site and the species are listed in Appendix 3 Section 1 . Tom thought more and larger pools existed on the land currently planted to grapes north of the mapped pools . Vernal pools are visible on the air photos and it is likely more vernal pools will be found during a thorough inventory, particularly on the northwestern portion of the savanna. Vegetation of the Lake Margins A distinct but non-continuous band of vegetation is found along the margins of the ephemeral lakes . In some places the vegetation consists of extensions of the savanna species however in other places it is distinctly riparian. Cottonwood, willow, buttonbush, and valley oak are common in several size classes, blue, valley and interior live oaks are located on the upland edges of this woody vegetation types . If one or both of the lake beds contain water on a more permanent basis wetland species will naturally increase in number and density. The band of riparian vegetation will thicken, eventually resembling areas updrainage from the two ephemeral lakes . Sapling-sized oaks and willows were numerous . Reduction of grazing and time will eventually completely restore the vegetation. The amount and types of vegetation will be enormously constrained by the amount and kind of water held in the lakes and the length of time water will occupy the lakebeds during the year . The owners are discussing methods of enhancing waterfowl habitat with Ducks Unlimited. 7