Ill. Admin. Code tit. 8, § 900.807 – Targeted Crop Yield Goal

a) The targeted crop yield goal, as required in Section 900.803(m)(6) of this Part, shall be determined for each field where the livestock waste is to be applied. The targeted crop yield goal shall be determined by obtaining an average yield over a five-year period from the field where livestock waste is to be applied. The following listing of sources of data shall be utilized to determine the targeted crop yield goal.
1. 1) Proven yields. The proven yield shall be determined by obtaining an average yield over a five-year period from the field where livestock waste is to be applied. The owner or operator shall indicate the method used to determine the proven yield. Data from years with crop disasters may be discarded. Proven yields shall be used unless there is a sound agronomic basis for predicting a different targeted crop yield goal;
2. 2) Crop insurance yields. A copy of the crop insurance yields shall be included in the plan; or
3. 3) Farm Service Agency – United States Department of Agriculture yields. A copy of the assigned crop yields shall be included in the plan.
b) Soils based yield data from the Natural Resources Conservation Service of the United States Department of Agriculture shall be used if the owner or operator cannot obtain a targeted crop yield goal pursuant to subsection (a) of this Section. A soil map of the application areas shall be included in the plan. The targeted crop yield goal shall be determined by a weighted average of the soil interpretation yield estimates for the areas that will receive livestock waste.
c) Nitrogen and phosphorus fertilization rates for the targeted crop yield goal may be obtained from the Illinois Agronomy Handbook, or 35 Ill. Adm. Code 560, Appendix A.