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Ecological Evaluation of Brovelli Woods P.C. Muick Oak Forests along the Mokelumne River For purposes of the vegetation analysis I divided the oak forest bordering the Mokelumne River into two sections as illustrated in Figure 3 . The western section contains the fairways and has potential for a small preserved forest area of about ten acres . The eastern section is the undisturbed forest east of the fairways. The forest was evaluated using plots and air photo interpretation. During my first walk through the forest I observed the vegetation mosaic, varied microtopography and overall heterogeneity of the forest. Collecting data, although costly in terms of time, is useful in quantifying the structure of the forest and also for interpreting air photos. Since the presence of the riparian oak forest precipitated this ecological analysis and is considered the major ecological value of the property I decided to quantify the forest structure. The locations of the plots were roughly mapped before going into the field to represent the spatial diversity of the forest. Data from ten circular plots , each having an area of one-hundred square meters , were collected. By design I avoided sampling the oxbows and meanders where cottonwood and buttonbush were located , not because I considered them less important species but because these areas were much smaller in proportion to the area of the dominant oak vegetation. The air photo interpretation was a visual analysis based on a series of air photos obtained from the San Joaquin County Department of Public Works and two recent photos lent by Kjeldsen-Sinnock. The dates of the photos are: June 1940 , August 1952 , June 1963 , November 1975, January 1983, February 1986 and October 1987. In the following four sections I describe the two forest areas , topography, vegetation, forest structure, density and diversity then compare the two forest areas , and discuss the air photo evidence. Western Forest The gently rolling 52 acres composing the western section contains deposition areas , surface drainage features and at least one large oxbow. Six of the ten survey plots were located in this section (Numbers 1-5 , and 10 see Map 1 ) . The total area of the plots was . 15 acre for a . 003 percent coverage of the section. In addition to surveying , I counted the rings of five tree stumps (cut for the fairways) , determined the species and photographed the cross sections . Much valuable information about stand age and dynamics could still be gathered through analysis of the rings on the cut stumps. Interior live oak, valley oak, box elder , a few sapling buckeyes , cottonwood, buttonwillow and ash were observed. The average cover of trees in this section was 92 percent, shrub cover averaged seven percent and cover of herbaceous species 53 percent. Approximately five vines ( lianas ) of grape and poison oak were found on each plot. The diversity of plant species averaged seven species per plot. A complete list of the species found on the plots is contained in Appendix 3 : Section 2 . Table 2 summarizes the number of stems per plot, average diameter and heights of trees , the average number of seedlings and saplings . Surveying the six plots took approximately three hours . 8