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vegetation with herbicides around broad - leaved species like aspen presents additional <br />• constraints. <br />We investigated this question by continuing to mechanically control competing <br />vegetation around trees in half of each irrigation and soil treatment. Treatments in the <br />fenced plantation area were divided into sections to be weeded and sections not weeded. <br />The two weeding treatments were superimposed on the existing study design; and <br />growth, physiological parameters, and survival were compared as in other treatments. <br />Soil samples were collected from each treatment for moisture content analysis. <br />EXPERIMENTAL RESULTS <br />Aspen growth and survival on reclaimed lands was successful under certain conditions. <br />The experiment was conducted 2005 -2007 on the II -W Mine plots, Seneca Coal <br />Company, near Hayden, CO (Figure 1). This report examined third year growth and <br />survival of these trees. <br />Growth by irrigation treatments and plant type: <br />Saline water inhibited the growth of aspen on high and medium irrigation treatment plots <br />the first and second year of the study. These trees were still smaller in the third year but <br />their annual growth had nearly recovered to that of low and control irrigation treatments <br />(Figure 3). Growth of the low irrigation and control (no irrigation) treatment trees was <br />higher than that for the high and medium irrigation treatments suggesting that the reduced <br />. growth from the saline water used for irrigation in the first and second years of the <br />experiment was still evident in the third year of treatment. Nevertheless, growth of these <br />trees was still greater than that for the natural sprouts and potted trees. None of the trees <br />that had died in previous years re- sprouted from residual roots in 2007. Since growth of <br />aspen was good with the low and no irrigation treatments, it is evident that there was <br />sufficient natural rainfall during the three years of the study for the trees to survive <br />without irrigation. It is possible that growth under the high irrigation treatment could <br />have been higher than the lower irrigation treatments had clean water been used. The <br />benefit of clean water irrigation of newly planted trees under more normal, low rainfall <br />conditions could not be determined in this experiment since low rainfall and drought <br />conditions did not occur during the study. <br />Growth of the transplanted trees was generally good during the third year of treatment <br />and surpassed that of the natural sprouts and potted trees (Figure 3). Survival was similar <br />for all transplants and natural sprouted trees (50 -57 %), but was considerably higher for <br />potted plants (80 %). Growth and survival of the potted trees was excellent the first year <br />of the study, but after three years growth of the potted trees remained relatively stagnant <br />and these trees were considerably smaller than the transplanted trees. Growth of natural <br />sprouts was also less than <br />transplants after three years. <br />Differences in soils: <br />