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Data Collected: <br />Prior to bud break, height of each tree, number of branches, disease and insect <br />infestation, and length of terminal leader dieback was recorded for each tree. Water <br />status and tree growth were measured periodically throughout the experiment. <br />Physical measures of growth were height (cm), basal caliper (mm), number of basal <br />sprouts (count), length of the terminal leader (cm), and length of each of the next <br />three sprouts on upper portion of tree (cm). Disease and insect infestation were <br />recorded again at the end of the growing season. <br />Water status, or leaf water potential, of the plants was measured on June 22, July <br />21, and September 20 as near to dawn as possible ('/z hr predawn to'/z hr after <br />sunup) to capture the minimum stress before rapid morning transpiration has <br />depleted leaf moisture. One afternoon measurement was also conducted on August <br />18 to indicate maximum stress under high radiation loading when transpiration would <br />be highest. Treatment, ambient temperature, time of sampling and exuding pressure <br />level was recorded. Leaves were collected from the different treatments at random <br />to minimize time of sampling biases. <br />Leaf water potential will increases as water is withheld from the plant and plant water <br />stress increases. Water status measurements required removing one fully matured <br />leaf randomly selected from trees in each treatment and measured for water holding <br />capacity using a Plant Water Status Console. The leaf was removed from the plant <br />and immediately placed in a sealed chamber with the petiole extending through a <br />sealing hole in the chamber. A fresh slightly angled cut was made and nitrogen gas <br />was delivered to the leaf under slowly increasing pressure until water exudes from <br />the petiole surface. The pressure necessary for this to occur is an indication of the <br />leaf water potential or water holding capacity of the leaf, an indication of the water <br />stress and thus physiological stress of the plant. Different plants from each treatment <br />were selected at each testing to minimize leaf loss from sampling. From 2-3 total <br />measurements were made from each treatment each day of measurement. Number <br />5 <br />