a. Plant Community Identifications . Initially, the study area 

 was traversed extensively to gain a general overall impression of its 

 vegetational diversity. An east-west base line was then established 

 along the southern boundary of the study area, using a transit and 

 stadia rod (elevations were not determined) . Nine north-south line 

 transects were than run from the base line at 300- foot intervals. 

 Vegetational descriptions were made along these transects, and nine 

 distinct community types were defined; two additional community types 

 were later added. 



bo Community Sampling s The subjective community identifications 

 verified observations made prior to the initiation of this investigation. 

 Only two physiognomically distinct vegetational were identified: (a) 

 Areas dominated by grasses and forbs, and (b) areas dominated by shrubs 

 (some with trees associated) . 



Previous experience with similar vegetational types has demonstrated 

 that 0.2- by 0.2-meter-square quadrats arranged in a stratified random 

 manner will produce statistically valid results in grass-dominated and 

 forb-dominated vegetation (Levy, 1970). Good results can be obtained 

 using 1- by 1-meter-square quadrats in shrubby vegetation and 4- by 4- 

 metej-square quadrats in areas dominated by shrubs and small trees. 



Several techniques were used to determine the nvunber of plots 

 required for a statistically adequate sample. A running mean was 

 determined for important species in each community by plotting, the 

 value obtained for a dominant species in the first sample quadrat 

 and the mean of plots 1 and 2, 1, 2, and 3, etc. A sample was judged 

 adequate when the regression line generated by this procedure no longer 

 varied more than 10 percent from previously obtained mean values for 

 the population. Five plots were sampled in shrub -dominated communities 

 and 20 in grass-dominated communities prior to running mean analyses; 

 this procedure was conducted for two or three dominant species in each 

 community. Enough samples were obtained to ensure adequate sampling 

 of all dominant species. In all cases, rarer species (those with low 

 frequency of occurrence in the sample plots) were inadequately sampled. 

 Results were verified by examining variance, mean, and standard error 

 of the populations. All methods indicated that adequate data had been 

 collected for a reliable quantitative description of the various 

 vegetational types. 



The sound-side shrub community appeared to require only five quadrats 

 for an adequate sample. Frequency data were collected from five 

 additional random plots to ensure sampling adequacy. The results of 

 the five initial plots were compared to the data collected for all ten 

 plots, using a chi— square test. The value obtained was less than the 

 0.05 level of confidence, demonstrating that no significant difference 

 occurred between these two sets of data. Therefore, the first five 

 samples were used to represent this community. 



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