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<br />by 7 meter belt transects were run in each herbicide treatment area. All <br />other treatments had 14 transects each, ranging in size from 2 by 16 meters <br />to 7_ by 25 meters. 1987 data was collected between August 27 and September <br />16. <br />The shrub density data was analyzed by use of a SAS statistical program <br />on an IBM main frame computer. Analysis of variance and Duncan's multiple <br />range test were used to determine significant differences at the .05 level. <br />Two separate analyses were run because not all treatments are crossed. As <br />can be seen on the study plot layout Figure 1, one lift treatments are <br />nested in fall treatments. One analysis consisted of all fall treatments <br />and the other of all 2 lift treatments. <br />RESULTS <br />The shrub density results for each treatment are summarized in Tables <br />1-3. Tables 4 & 5 contain a summary of the statistical analyses. <br />Comparison of the 1987 data with the results of the data collected in <br />1986 at the end of the first growing season (see 1986 Progress Report) show <br />a 38% decline in total shrub density. This decline was a result of <br />significant reductions in aspen (70%), chokecherry (52%), and serviceberry <br />(48%). Snowberry, rose, currant and other species have shown small <br />increases. <br />The most significant treatment difference remains summer verses fall. <br />Shrub densities of summer treatments (1223/acre) remain more than double <br />those of fall treatments (600/acne). Summer treatments were statistically <br />superior at the .05 level for 3 of the 5 species, including, aspen, <br />Snowberry and rose. Chokecherry and serviceberry also had higher mean shrub <br />densities for summer treatments although not statistically significant at <br />tfie .05 level. <br />Differences between rotoclearing and dozing were much less clear, with <br />some significant departures from last years results. 1986 results showed a <br />clear preference with higher densities for most species on rotocleared <br />sites. This year there has been a shift to higher densities on dozed sites <br />however, this is not consistent for all treatments or all species. The most J <br />