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treatment, and both of these had higher soil moisture than the low and no irrigation <br />treatments (Figures 4b, 5a, 5b), verifying the effectiveness of the irrigation treatments. <br />However, there appeared to be no benefit to soil moisture over natural rainfall with the <br />low irrigation treatment in the dozer-cleared/fresh soils (Figures 5a, 5b). <br />The dozer-cleared/stored soil was not as well drained, as evident by the apparent <br />greater retention of water in these soils than in the roto-cleared soils (Figures 4a, 4b, <br />5a, 5b). This was also apparent from the accumulation of water in a soil pit downhill <br />from the plot during periods of heavy rainfall vs no water accumulation in a similar pit <br />downhill of the roto-cleared/fresh soil. This also appears to be confirmed by the higher <br />soil moisture at deeper vs shallower depth in the dozer cleared soils, compared to the <br />reverse relationship in the roto-cleared soils (Figure 5a, 5b). Non-irrigated dozer-cleared <br />soil generally retained more moisture than non-irrigated roto-cleared soils (Figures 4a, <br />4b, 5a, 5b). <br />Aspen growth did not respond to irrigation as expected in either soil type. Growth <br />seemed to be negatively related or un-related to the amount of water delivered to the <br />plants, depending on the growth variable (Figures 6a, 7a, 8a, 9a, 10a). Survival was <br />lower in those plots receiving the highest irrigation treatment (Figure 11 a). It was <br />observed after the first year of irrigation in 2005 that salt buildup was evident on the soil <br />surface of the irrigated trees; and it appeared that salt on the soil surface seemed to be <br />more obvious in the treatments with the highest amount of water added. The primary <br />source of irrigation water during 2005 was the first main pond to the right of the road <br />after entering the main road to the II-W mine from County Road 53, at the beginning of <br />the S-curve, down slope from the experimental site (see Pond on map, Figure 1). <br />During the 2006 season, it was expected that water would be obtained from different <br />sources than during 2005. Upon further investigation, it was determined that most of the <br />water for irrigation during 2006 came from the same holding pond as during 2005, the <br />pond on the lower portion of the main road to the II-W mine. Total dissolved solids of <br />water from this pond was 3722 mg/L in 2006 (data from Seneca Coal Company), <br />equivalent to an electric conductivity (EC) of greater than 4 dS/m. <br />Electric conductivity (EC) measured from soil samples collected at the <br />experimental site indicate that those soils with the highest irrigation treatment were the <br />13 <br />