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• height (dbh), however most aspen are typically much younger and smaller. Many <br />mature stands in Colorado are currently over 120 years of age (Shepperd 1990). Tree <br />form varies from shrubby at upper and lower forest margins to over 100 ft (30.5 m) in <br />height in prime locations with average heights of 50 to 60 ft (15 to 18 m) (Baker 1925). <br />In any case, the initiation of bud growth must also be accompanied by sufficient <br />sunlight and warmer soil temperatures to allow the new suckers to thrive (Navratil <br />1991, Doucet 1989). Full sunlight to the forest floor best meets these requirements. <br />However, young aspen suckers are susceptible to competition from other understory <br />plants and herbivory from browsing ungulates (primarily elk and deer in Colorado) even <br />if abundant suckers are present. <br />Having access to a well developed parental root system gives aspen sprouts a <br />great advantage over other plants. The parent roots supply carbohydrates and access <br />water deep in the soil profile allowing sprouts to grow rapidly, out - compete other <br />vegetation, and withstand frequent droughty conditions in the West. <br />0 Serviceberry, like aspen, depends on sprouting for reproduction, is difficult to <br />start from seedlings, and has been shown to be difficult to reproduce on reclaimed mine <br />lands (Agnew 1992). Movement of topsoil containing roots for sprouting to the <br />reclaimed site (livehauling), or transplanting of native plants, provided for the best <br />establishment on reclaimed mine lands (Agnew 1992). The influence of competing <br />vegetation on establishment of serviceberry on reclaimed lands has not been studied. <br />Planting aspen in a non - irrigated location in a Colorado study was not successful <br />(Shepperd and Mata 2005). Transplanting greenhouse or nursery -grown aspen seedlings <br />into the field has similar problems to those of natural seedlings, indicating that the small <br />root mass of transplanted seedlings is insufficient to absorb enough moisture to <br />maintain the seedlings during periods of summer drought in the wild. Re- establishing <br />aspen and serviceberry on reclaimed surface -mined lands is therefore problematic, <br />since the parent root systems are destroyed when topsoil is removed. <br />In contrast, transplanting sapling -sized aspen in irrigated urban landscapes has <br />not been a problem, because the abundant supplies of water in lawns and landscape <br />4 <br />