Lesson 31: Manure Utilization Plans

Manure Nutrient Availability


Table 31C-1: Land requirement for manure N.

Available Manure N (Table 31-5) = lbs N

B. Field ID C. Acres D. Crop E. Yield Units F. Crop N Requirement1 G. N Credits2 H. Manure N Requirement (= F - G) I. Manure N Use by Field (=C * H) J. Remaining Manure N (A - I)3
1Crop N Requirements should be based upon historical soil tests and/or recommendations. If this information is not available, crop N removal rates are an alternative. For the corn example, Crop N Removal equals 170 bu./ac. * 0.9 lb N/acre or 153 lbs of N/acre.
2Nitrogen credits should include commercial fertilizer use, legume credit, or residual soil credit (if not already discounted by soil test recommendation).
3Remaining Manure N is calculated for the first field by subtracting "Manure N Use by Field" from "Available Manure N." For all remaining fields, it is calculated by subtracting "Manure N Use by Field" from the "Manure N Remaining" results of the previous field.

Table 31C-2: Land requirement for manure P.

Available Manure P (Table 31-3) = lbs P

B. Field ID C. Acres D. Crop E. Yield Units F. Crop P Requirement1 G. P Credits2 H. Manure P Requirement (= F - G) I. Manure P Use by Field (=C * H) J. Remaining Manure P (A - I)3
1Crop N Requirements should be based upon historical soil tests and/or recommendations. If this information is not available, crop N removal rates are an alternative. For the corn example, Crop N Removal equals 170 bu./ac. * 0.9 lb N/acre or 153 lbs of N/acre.
2Nitrogen credits should include commercial fertilizer use, legume credit, or residual soil credit (if not already discounted by soil test recommendation).
3Remaining Manure N is calculated for the first field by subtracting "Manure N Use by Field" from "Available Manure N." For all remaining fields, it is calculated by subtracting "Manure N Use by Field" from the "Manure N Remaining" results of the previous field.

Table 31C-3: Land requirement for anaerobic lagoon sludge P.

Available Manure P (Table 31-4) = lbs P

B. Field ID1 C. Acres D. Crop E. Yield Units F. Crop P Requirement2 G. Years of Crop P Needs to be Supplied3 H. Sludge P Use by Field (= C * F * G) I. Remaining Sludge P (A - H)4
1Fields not receiving regular manure applications should be selected for sludge application.
2Crop P Requirements may be based upon historical soil tests and/or recommendations or crop P removal rates (select larger value). For the corn example, Crop P Removal equals 170 bu./ac. * 0.36 lb N/acre or 61 lbs of N/acre.
3If soil P levels are near or below agronomic rates, it may be desirable to build soil P levels by applying sufficient P to supply several years of crop needs.
4Remaining Manure P must be calculated for the first field by subtracting "Sludge P Use by Field" from "Available Sludge P." For all remaining fields, it is calculated by subtracting "Sludge P Use by Field" from the "Sludge P Remaining" results of the previous field.

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