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metric tons/ha, for the subsoil only treatment and 2.11 metric tons/ha for the 60 -cm <br />topsoil over 70 cm of subsoil treatment. On the mixed topsoil/subsoil soil treatment <br />production of Alfalfa was highest, 1.92 metric tons/ha at the 110 -cm depth. <br />Statistically, there was no difference in Alfalfa production at thickness of respread <br />subsoil up to 50 cm or for the mixed topsoil/subsoil soil treatment where Alfalfa <br />production peaked at the 130 -cm depth and then declined at greater depths of <br />respread soil material. These researchers concluded by stating that "at least 90 <br />percent of maximum" yields could be obtained "with at least 90 cm of the mixed <br />subsoil - topsoil spread over spoils." The also determined that "at least 90 % of <br />maximum yield of all crops except wheat were obtained without separating topsoil <br />and subsoil into discrete layers." <br />In a followup study of the same plots performed in 2003, 28 and 299 years after plot <br />establishment, Wick and others (2005) documented the long term effects of respread <br />soil materials and plant community development on two wedge studies, started in <br />1974 and 1975, respectively. Findings of their study clearly revealed that forage <br />production was significantly higher over time for both grasses and Alfalfa when the <br />1978 data were compared to the 2003 data. With respect to Smooth Bromegrass, <br />they reported that after 28 years, highest production was found on the 60 to 120 cm <br />total soils depths, but that the data where not statistically significant when <br />compared to the 0 to 40 cm depths. For Alfalfa, highest production was associated <br />with the mid slope plots where the depth of reapplied soil was 60 to 120 cm. Total <br />depth of respread soil was found to have a statistically significant effect on plant <br />growth after 28 years, but these authors concluded that "plant community <br />production is no longer as dependent upon soil depth" and that other soil factors <br />might now have a stronger influence of forage production than does soil depth. <br />These researchers concluded that "the long -term relationships established among <br />plant comminutes, total soil depth and soil characteristics on reclaimed lands were <br />very different from the relationships observed during initial vegetation <br />establishment." <br />The text in Appendix 2.05.4(2) (d) -1 (CSU Study) and Appendix 2.05.4(2) (d) -3 (Plateau <br />Study) corresponding to these two topsoil segregation studies will be deleted. Inserted <br />in their place in Appendix 2.05.4(2)(d) -1 will be the article by .1. F. Power, F. M. <br />Sandoval, R.E. Reis and S.D. Merrill. 1981 entitled, "The Effects of Soil Depth and <br />Other Soil Characteristics on Plant Community Development in North Dakota. Pages <br />1233 to 1243 in 2005 National Meeting of the American Society of Mining and <br />Reclamation" and in Appendix 2.05.4(2)(d) -3 will be the article entitled "Effects of <br />Topsoil and Subsoil Thickness on Soil Water Content and Crop Production on a <br />Disturbed Soil. Soil Science Society of America Journal Vol. 45:124 -129 and A. F. <br />Wick, S. D. Merrill, T. J. toy, J. Henderickson and M.A. Liebig. 2005" <br />Page 28 <br />