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zz <br />burnet, on the other hand never became an important component of <br />• the seeded community and was eventually excluded from the site by <br />1990. <br />Comparisons with the Ondisturbed Native Community <br />Percent canopy cover and aboveground production of herbaceous <br />species and density of shrubs were estimated in the undisturbed <br />plant community in 1985 (unpublished data). The results from this <br />sampling indicate the herbaceous canopy cover averaged 56$, <br />aboveground production averaged 96 g/mz, and shrub density averaged <br />18 plants/m2. Results from the 1990 sampling of the test plots <br />indicated that herbaceous canopy cover averaged 52$ with a high of <br />56~ on the 30 cm treatment and a low of 50~ on the 45 and 60 cm <br />treatments. Herbaceous production on the test plots averaged 263 <br />• g/m2 with a high of 298 g/mz on 60 cm of topsoil and a low of 232 <br />g/mZ on 45 cm of topsoil. Finally shrub density on the study site <br />was less than 0.1 plant/mZ on the 15 cm treatment which supported <br />the highest density of shrubs. <br />It appears from this comparison that all of the topsail <br />treatments tested support an equivalent or greater level of <br />herbaceous canopy cover and aboveground production as found in the <br />native community. In fact, the test plots supported three times <br />more herbaceous production than the native community. Shrub <br />density, on the other hand was some 18 times lower on the test <br />plots than in the native community. The treatments being tested <br />still supported a grass dominated community after ten years, while <br />the native community is dominated by shrubs. <br />