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placed in each of two types of topsoil that had been removed from areas being prepared <br />for surface mining. <br />Roto - cleared topsoil had the original vegetation on the site chopped and mixed into the <br />top 4 inches of topsoil prior to removal and replacement on the plantation site. Dozer <br />cleared soils had all above -ground vegetation bladed aside for disposal prior to removal <br />and storage before replacement on the plantation site. The dozer cleared soil used in this <br />study had been stored for a few months, as indications of decay were present and few <br />weeds initially grew in this soil. Both soil types were from aspen stands, contained aspen <br />roots and were placed to a depth of approximately 1 m on the plantation site. The soils <br />were spread by scraper in the late summer of 2003, and were final graded in May /June of <br />2004, prior to aspen planting in October, 2004. <br />Water was delivered during the 2005 growing season by drip irrigation to the <br />transplanted aspen saplings via a computer - controlled system that timed the daily <br />application of water through calibrated emitters. The four water treatments (high, <br />medium, low, non - irrigated control) were randomly assigned to one of the four blocks in <br />each of the two soil types, with all 50 trees in each block receiving the same amount of <br />water (Figure 2). A gravity fed drip system, supplied by a 2000 gallon tank located 207 <br />vertical feet upslope from the test site provided an adequate head to maintain water <br />pressure greater than 60 lbs in all lines. The tank was filled by Seneca Coal Company <br />workers as needed, generally once or twice a week. Source of water was a sedimentation <br />pond lower in the reclaimed watershed. Drippers delivered water at 1 gallon/minute, and <br />were programmed to deliver water daily at 1.3, 0.6, and 0.3 gal/day /tree for the high, <br />medium, and low irrigation levels; equivalent to 14.4, 7.2, and 3.6 inches of precipitation <br />per month. <br />The non - irrigated control received no supplemental water. Irrigation treatments were <br />applied daily during the early morning. Drippers required 4 lbs pressure for activation; <br />the valve box and distribution lines were configured so that head pressure down stream of <br />the valves did not exceed this value to avoid leakage between irrigation treatments. Soil <br />moisture and temperature sensors were located in each plot and data were recorded <br />hourly. Standard meteorological conditions were monitored at an automated weather <br />station located at the center of the plot, and data recorded hourly included wind speed, <br />wind direction, relative humidity, and precipitation. Hourly soil temperature, moisture <br />content, and matrix potential were also monitored at one tree in each watering treatment. <br />All data were recorded on a Campbell 23x data logger, which also was programmed to <br />activate the irrigation solenoids. Power was supplied from 12 V batteries charged by a <br />solar panel. <br />In addition to the watering study, growth and survival data were obtained from three <br />other types of young aspen trees: <br />1) Natural sprouts that had grown from roots buried in un- irrigated areas of the roto- <br />cleared and dozer - cleared soil adjacent to the irrigated blocks; <br />s <br />