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Table 7. Shrub densities for Topsoil Depth Study (Topsoiled) Plot 95-4B. Species 1997 Density per Acre Spring 1996 Density per Acre* 1997 Density per Hectare Spring 1996 Density per Hectare 1997 Frequency % Survival** Serviceberry 333 687 823 1700 100% 48% Chokecherry 518 639 1280 1579 100% 81% Gambel's Oak 356 487 880 1200 100% 73% Totals 1207 sd=421 1813 sd=364 2983 sd=1041 4479 sd=900 100% 67% sd=standazd deviation * 1997 data aze compared against 1996 data. Snowpack in 1995 prevented an accurate count for baseline compazison. **Survival based on original number of individual plants per transect. Location: Planting Unit 95-4 is divided into two sepazate units as part of an ongoing Topsoil Depth Study. Planting Unit 95-4B is on the topsoiled portion of the study site. The baseline runs along the west border of the site (B°, B44) with endpoints at metal posts marked with aluminum tags. Transects are perpendiculaz and located at 6, 12, 16, 20, 24, 28, 30, 34, 38, and 40 meters. Endpoints of the transects aze marked with wooden stakes. Herbaceous Cover: Grass = 0.0% coverage. Forb = 11.5% coverage. A substantial number of Canada Thistle (Cirsium arvense) seedlings were noted on the site. The thistle will present a future weed problem. Comments: Overall, the percent survival dropped to 67% in 1997. Gambel's Oak and Serviceberry exhibited the most substantial 'drop with greater than 20% loss of individuals during the 1997 growing season. The cause for such a drop is potentially related to weed competition. Many large thistle were observed crowding and in some cases completely covering the seedlings. The thistle population was substantially lazger than previous monitoring. The soils of the plot aze generally bare and have higher nutrient values than the non-topsoiled plot, and thus, the weeds take advantage of the lack of competing cover, especially the Canada Thistle plants. Thistle coverage varied dramatically between topsoil and non-topsoil plots. 11