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on a 1.5 m x 1.5 m grid (Figure 1). Four blocks were placed in each of two types of topsoil that had been removed from areas being prepared for surface mining. Roto-cleared topsoil had the original vegetation on the site chopped and mixed into the top 4 inches of topsoil prior to removal and replacement on the plantation site. Dozer cleared soils had all above-ground vegetation bladed aside for disposal prior to removal and replacement on the plantation site. The dozer cleared soil used in this study may have been stored for a few months, as indications of decay were present and few weeds grew in this soil. Both soil types were from aspen stands, contained aspen roots and were placed to a depth of approximately 1 m on the plantation site. The soils were spread by scraper in the late summer of 2003, and were final graded in May/June of 2004, prior to aspen planting in October, 2004. Water was delivered during the 2005 growing season by drip irrigation to the transplanted aspen saplings via acomputer-controlled system that timed the daily application of water through calibrated emitters. The four water treatments (high, medium, low, non-irrigated control) were randomly assigned to one of the four blocks in each of the two soil types, with all 50 trees in each block receiving the same amount of water (Figure 1). A gravity fed drip system, supplied by a 2000 gallon tank located 207 vertical feet upslope from the test site provided an adequate head to maintain water pressure greater than 60 Ibs in all lines. The tank was filled by Seneca Coal Company workers as needed, generally once or twice a week. Source of water was a sedimentation pond lower in the reclaimed watershed. Drippers delivered water at 1 gallon/minute, and were programmed to deliver water daily at 1.3, 0.6, and 0.3 gal/day/tree for the high, medium, and low irrigation levels; equivalent to 14.4, 7.2, and 3.6 inches of precipitation per month. The non-irrigated control received no supplemental water. Irrigation treatments were applied daily during the early morning. Drippers required 4 Ibs pressure for activation; the valve box and distribution lines were configured so that head pressure down stream of the valves did not exceed this value to avoid leakage between irrigation treatments (Figure 1). Soil moisture and temperature sensors were located in each plot and data were recorded hourly. Standard meteorological conditions were monitored at an automated weather station located at the center of the plot, and data recorded hourly included wind speed, wind direction, relative humidity, and precipitation. Hourly soil temperature, moisture content, and matrix potential were also monitored at one tree in each watering treatment. All data were recorded on a Campbell 23x data logger, which also was programmed to activate the irrigation solenoids. Power was supplied by 12 V batteries charged by a solar panel. In addition to the watering study, we also obtained growth and survival data from three other types of young aspen trees: 1) Natural sprouts that had grown from roots buried in un-irrigated areas of the roto-cleared and dozer-cleared soil adjacent to the irrigated blocks; 2) commercially-grown potted aspen seedlings that were planted in an unirrigated fenced area approx 1 km from the irrigation study site, and; 3) natural aspen sprouts growing in an un-mined area of the Yoast mine that had been cleared of mature aspen. None of these study sites were replicated, so the survival, growth, and water status findings are applicable only for that site; and comparability of different un-replicated treatments within the same site must be made with caution. Although the commercially-grown potted aspen trees were planted on dozer-cleared soil, it was not determined if the roots grew out of the potting mix into the dozer- cleared soil during this first year of study.