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~~ Douglas Fir was planted on the roadside disturbances but not a single tree was still alive. In Williams Canyon, Douglas Fir was in excellent condition and actually showed the greatest amount of growth with Pinon lagging somewhat. The roadside disturbances, being north facing and therefore cooler and wetter than the west facing Williams Canyon slope, should be more adaptable for Douglas Fir. Yet Douglas Fv cannot survive on the roadsides and does well on the hotter and probably drier Williams Canyon Slope. Pinon, on the other hand, along the roadsides, does better than Juniper although by environmental condition the roadside disturbances should be most advantageous to Juniper. This puzzling and contrary pattern seems to indicate that a complex of factors are influencing tree growth along the roadside, a complex that is not present in Williams Canyon. Two other factors might be involved in this complex pattern. First, it should be noted that, in Williams Canyon the rolling rocks only affected the nature of the surface vegetation, but did not significantly affect the nature of the soils on the slope. Therefore, all the original soil and its characteristics, including microbiology, was still present when the trees were planted. Along the roadways, although soil was spread, the soil structure and microbiology was very different from its original condition. Therefore, tree plantings into Williams Canyon had available all the necessary ingredients to establish a comparatively similar vegetation growth to what was originally there. On the roadsides though the soil endvonment was totally altered and might not in fact support the kind of tree growth originally there until soil development processes can create those conditions again. Second, the microbiological differences between W illiams Canyon and the roadside disturbances is undoubtedly very different. All the native vegetation is still in Williams Canyon, although in different numbers than the original condition. It would be expected then, that whatever is necessary to support, for example Douglas Fir, was still present when the trees were planted. On the roadsides, little if any of that supporting microbiology was present when the trees were planted and therefore most of the trees (all the Douglas Fir) promptly died. It might be easy to conclude that insufficient water on the roadside disturbances resulted in the demise of most of the trees, but because the slopes face north the moisture regime should be higher than it is in Williams Canyon where tree planting was successful. A conclusion that there is too much water along the roadsides (the trees were drowned) is inconsistent with the presence of good forest adjacent to the disturbances. As for competition, that is a possible factor in the death of the trees along the roadside, but actually the competition for moisture is probably greater in Williams Canyon. Not only is grass density often comparable between the two areas, in Williams Canyon there is abundant shrub growth that is often even more competitive with trees than grasses. Most of that shntb growth is Gambel Oak which Additional Sheet Snyder Quarry 1994 Annual Report Page 3