### University of Missouri Extension

EQ392, New April 2003

# Economic Considerations for Beef Manure Management Systems

## Example 1

Determine the value of the three types of manure for a corn-soybean rotation with the following soil test recommendations: For 150 bushels per acre corn: 195 pounds N, zero P2O5 and 60 pounds K2O. For 40 bushels per acre soybeans: zero N, zero P2O5 and 75 pounds K2O (soil test results were 116 [very high] for phosphorus, 280 for potassium, and 2.9 for organic matter).

The last crop was soybeans, so we can take credit for 30 pounds N from the soybeans and apply 165 pounds of N for corn.

Using all the slurry manure from 150 head (Table 20), the available N is 3,420 + 6,045 = 9,465 pounds of N; the available P2O5 is 8,250 pounds x 0.95 = 7,838 pounds; and the available K2O is 11,850 pounds x 0.95 = 11,258 pounds. With 9,465 pounds of available N, we can apply 165 pounds of N to 57 acres. Using all the manure will also apply 8,250 pounds of P2O5 and 11,850 pounds of K2O (Table 20). For the 57 acres of corn, the soil test calls for zero P2O5 and 3,420 pounds K2O. No return should be expected from the 8,250 pounds of P2O5 . To have 3,420 pounds of K2O available, we must apply 3,600 pounds at 0.95 percent availability. Adding the value of 9,465 pounds of N at \$0.30 per pounds = \$2,840 to the value of 3,420 pounds of K2O at \$0.15 per pounds = \$513, the total value is \$3,353. If all the P2O5 and K2O applied had been needed, the value would have been \$6,096 (Table 20).

For soybeans and applying the solid manure at a rate to supply 75 pounds of K2O per acre, the 11,258 pounds of available K2O will fertilize 11,258/75 = 150 acres of soybeans. Since the soil test did not call for any N or P2O5 , the only value to be credited to the manure is for 11,258 pounds of available K2O at \$0.15 = \$1,689 (Table 20).

Caution
Since the soil test P is very high, any addition of manure increases the risk of downstream pollution from phosphorous and may not be allowed under developing regulations.

Table for example 1
Value of manure nutrients used by 150 bushels per acre corn (based on soil test)

Herd size (1,000-pound animals)
150 300 600
Gross value of excreted manure \$12,542 \$25,084 \$50,168

Value of lagoon N at 165 pounds per acre

\$732 \$1,463 \$2,927
Application acres 15.0 30.0 59.0
Value of P2O5 used by corn 0 0 0
Value of K2O used by corn \$135 \$270 \$531
Value of lagoon nutrients used \$867 \$1,733 \$3,458
Value of slurry N at 165 pounds per acre \$2,840 \$5,679 \$11,358
Application acres 57 115 229
Value of P2O5 used by corn 0 0 0
Value of K2O used by corn \$513 \$1,035 \$2,061
Value of slurry nutrients used \$3,353 \$6,714 \$13,419
Value of solid N at 165 pounds per acre \$1,210 \$2,318 \$4,636
Application acres 24 49 98
Value of P2O5 used by corn 0 0 0
Value of K2O used by corn \$216 \$441 \$882
Value of solid nutrients used \$1,426 \$2,759 \$5,518
EQ392 Economic Considerations for Beef Manure Management Systems | University of Missouri Extension

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