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cutting measure on the reclaimed lands, does not meet the average annual crop production <br />requirmement of 4.25.5(3); and also carries with it significant risk of under estimating the true annual <br />yield as the ultimate measure to determine that prime farmland agricultural productivity has indeed <br />been restored. Below is an example of the negative consequences of relying on the first - cutting as <br />the measurement of success on prime farmlands instead of determining and using the annual yield for <br />this purpose. <br />Example <br />As requested by OSM, in a letter dated April 4, 2011, the NRCS State Soil Scientist <br />for Colorado provided estimates of the productive capacity of the pre- disturbance <br />soils present within the Morgan's prime farmland property. Using a weighted <br />average by soil yield based on information included within the NRCS's letter, OSM <br />calculates the weighted mean yield capability of the Morgan's prime farmland under <br />a high level of management to annually be approximately 5.37 tons /acre. This yield <br />number contrasts starkly with the 1.84 tons /acre production success standard <br />approved in the permit for the Morgan property. <br />Although the permit does not clearly describe in what manner the 1.84 tons /acre first <br />cutting standard could be justified as an annual production estimate, it is presumed <br />that the intent may have been that one could deduce to multiply the 1.84 value by 3 <br />(for three cuttings) to determine a reasonable estimate of annual yield potential. As <br />described in OSM's review report, such a presumption is not technically supportable. <br />However, for perspective, as an example of the negative affect that applying such a <br />presumption may have on accepting a success standard based on a single cutting for <br />each growing season and /or limiting the harvest yield on the reclaimed lands to a <br />comparative first - cutting, a review of studies conducted on irrigated alfalfa fields in <br />the Intermountain West are useful. <br />These studies demonstrate that yields are known to drop 25% or more from first - <br />cutting to second - cutting and by 50% between first - cutting and the third- cutting. <br />For an example of effect, one might presume that the 1.84 tons /acre is an accurate <br />estimate for a first cutting yield on the Morgan property. Using percent changes <br />between cuttings based on data from a 3- cutting Idaho trend study as an example, the <br />1.84 tons /acre first cutting could reduce to 1.38 tons /acre for the second - cutting and <br />reduce further to 0.92 tons /acre for the third cutting; summing to 4.14 tons /acre as the <br />annual yield standard for the reclaimed lands. The 4.14 tons /acre annual yield value <br />6 As noted in Appendix B, data presented in section 2.04.10, subsection 6.3 of the permit, and repeated in Table 2.04.10 -18 <br />- Permit studies conducted in 1999 - suggests a yield of 4.26 tons/ac may be more representative for an irrigated alfalfa <br />first cutting on the Morgan Property. <br />Appendix D - As reported in Table 2 in "Deficit Irrigation of Alfalfa for Water- Savings in the Great Plains and <br />Intermountain West: A Review and Analysis of the Literature," by R. Bradley Lindenmayer, Neil C. Hansen, Joe <br />Brummer, and James G. Pritchett published in Agronomy Journal, Vol. 103, issue 1, pages 45 -50. <br />8 <br />