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• The plot of total herbaceous production data from the 1995, 1997, and 1998 reclamation <br />azeas and September-July precipitation is shown collectively and individually in Figures 23 <br />and 24. The wllective plot reveals a third order polynomial as the best-fit curve with two <br />inflection points in the data range. A correlation coefficient of 0.8583 was obtained for <br />this data set, the same value as that for the collective production data and the January-July <br />precipitation data. Individual plotting of the 1995, 1997, and 1998 reclamation areas total <br />herbaceous production and September-July precipitation reveals the same wide variation <br />in best-fit curves and corcelation as found with the January-July precipitation regime. <br />Best-fit curves included a third order polynomial for the 1995 reclamation area, an <br />exponential for the 1997 reclamation area, and a straight line for the 1998 reclamation <br />azea. Correlation coefficients ranged from one (1995 reclamation azeas) to 0.1354 (1998 <br />reclamation areas). <br />Separating the 1995, 1997, and 1998 reclamation azeas from the total data set revealed <br />that the younger reclamation azeas illustrate greater variation in total vegetation cover and <br />total herbaceous production responses to precipitation than the older reclamation areas. <br />Collectively plotting the younger areas data revealed best-fit curves with low (total <br />vegetation cover) to moderately high (total herbaceous production) correlations. Plotting <br />the individua! reclamation areas further revealed that the younger reclamation areas <br />responded significantly differently to precipitation (as evidenced by the best-fit curves and <br />correlation coefficients). Variation deceased and correlation reliability increased with <br />stand age. While the form of the best-fit curves for total vegetation cover showed <br />• expected form, the correlation for the best-fit curves remained less than fifty percent. For <br />total herbaceous production, correlation was much greater for both precipitation regimes, <br />but the form of the best-fit curve revealed inflection points not expected for the parameter <br />in the field. <br />3.5 Summary otResults <br />A summary of the results from the data for all precipitation regimes, the two vegetation <br />parameters, and alt areas sampled would be appropriate. <br />In the Osgood sand reference azea, plotting total vegetation cover and September-July <br />precipitation over eight years yielded a third order polynomial as the best-fit curve with a <br />correlation coefficient of 0.9477 (Figure 5). Corresponding plotting for total herbaceous <br />production revealed the best-fit curve (third order polynomial) and highest correlation <br />coefficient (R2=0.8918) with the September-July precipitation regime (Figure 7). While <br />the form of the best-fit curve in the case of total vegetation cover met expectations based <br />on ecological theory, the curve form for total herbaceous production indicated inflection <br />points (and corresponding increases or deceases in production) within the data range, a <br />phenomenon not expected or observed in the field. <br />Plotting total vegetation cover within all reclamation areas by precipitation regime <br />revealed no significant difference in predictability of the best-fit curves and equations <br />(Figures 2 and 6). The corresponding plot of total herbaceous production values from all <br />-11- <br />