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I~ I, I li i~ On a per species basis, Gambel's oak had high survival rates on both treatments (no- topsoi1=84%; topsoil=71%) which were not significantly different from one another. Serviceberry and chokecherry survival rates were significantly higher on the no-topsoil treatment versus the topsoil treatment (p<0.05 ). Serviceberry survival was 62% on the no-topsoil treatment versus 38% on the topsoil treatment. Chokecherry was 82% on the no-topsoil treatment versus 31 % on the topsoil treatment. In general, chokecherry and serviceberry in the topsoil treatment plots have experienced the greatest rate of decline. Several factors potentially caused the mortality of these plants. Although mortality after planting due to transplant shock was expected, substantial mortality over a three yeaz period was not anticipated. Factors which aze potentially responsible for continued mortality on the site aze plant competition, browse damage, lack of rooting, and lack of microbial associates. The following sections address each of these factors. Pant Vigor. Vigor was assessed through shoot and root measurements. Shoot height has not increased significantly since the time of planting (Table B-1). Root length has, however, increased substantially since the time of planting (Table B-2). Neither factor was significantly different between treatments. Table B-I. Shrub heights on topsoil and no-topsoil treatments. Initial Height (cm) No-topsoil Treatment (cm) Topsoil Treatment (cm) Serviceberry 11.4 12.6 13.3 Chokecherry 13.0 ]2.4 12.6 Gambel's Oak 9.1 10.4 12.5 Table B-2. Root lengths on topsoil and no-topsoil treatments. Initial Length (cm) No-topsoil Treatment (cm) Topsoil Treatment (cm) Serviceberry 18.5 25.0 31.0 Chokecherry 18.5 27.7 29.7 Gambel's Oak 19.5 33.0 27.7 Lack of shoot growth is the result of browse by deer, elk, or rabbits. As discussed in the previous section, continuous browse on these sites will eventually result in increased mortality. This may 13