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replicated for this study. This study is considered a case study relevant only for this one location. Nevertheless, several observations are evident from the study that might be helpful for future aspen management and to identify areas for additional research. Irrigation treatment -Unfortunately for this experiment, rainfall was heavy during the study (Figure 2) and soil moisture was relatively high even in un-irrigated plots, as indicated by low soil moisture matrix potentials for all treatments (Figure 2). Aspen growth and survival did not appear to be dependent on, or in some cases consistent with, irrigation treatment, suggesting that soil moisture from the frequent rain events was sufficient even in the non-irrigated plots. The supposition of adequate moisture available to all trees is further evident in that there appeared to be no relationship between irrigation treatment and average leaf area (Figure 3A), total leader growth (Figure 4A), terminal leader growth (Figure 5A), stem diameter growth or caliper (Figure 6A), or survival (Figure 7A). Growth of second, third, and fourth lateral branches appeared to be similar for all treatments and data are not shown, but are reflected in total growth (Figure 4A). Pre-dawn leaf water potential levels also indicate moisture stress was generally less than 6 bars (0.8 mPa) pressure, and did not appear to be related to irrigation treatments (Figures 8A -11A). (Note: roto-cleared soils are designated "fresh" and scraped soils are designated "stored" in the figures, since the dozer-cleared soils appeared to have been stored for a period of time.) 11. Transplant type -The aspen saplings used in the irrigation study that were transplanted from the Yoast site exhibited considerably more injury and had considerably more disease infections than natural sprouts arising from buried root segments or potted plants (Table 1). Leaf area growth, leader growth, stem diameter growth, and survival were considerably less with these plants than with natural sprouts or potted plants. (Figures 3A - 7A, compared with 36 - 76, note differences in scale of A and B plots). Potted plants survival was 100% (Figure 76); but growth (Figures 46, 56, 6B), although apparently not as good as natural sprouts, appeared better than transplanted cuttings (Figures 4A, 5A, 6A). Natural sprouts on roto-cleared or dozer-cleared soil had only one terminal leader with no lateral shoots. lll. Soil type - Roto-cleared soil provided sufficient natural sprouting to provide an adequate stand of aspen trees, and these trees appeared to grow better and survival appeared higher than adjacent transplanted trees growing in the same soil. Dozer-cleared soil which may have been temporarily stored, had considerably lower numbers of natural sprouts than roto-cleared soil, and stocking was sparse (data not shown). Natural sprouts appeared to have greater total leaf area (Figure 36) and greater stem diameter growth (Figure 66) on roto-cleared soil than dozer-cleared soil, but terminal leader growth appeared similar on both soil types (Figure 5B). Natural root sprouts had no lateral branches. Leaves also appeared to be larger on these trees (data not shown). Nevertheless, these trees apparently experienced somewhat greater pre-dawn water stress in July and September than trees in the irrigated treatments, including the irrigated controls with no water added (Figures 9, 10).