Manure can be an excellent source of nutrients for forage crops, as it is readily available on livestock farms. The value of manure in crop production is often underestimated. Manure contains all the nutrients needed by crops but not necessarily in the proportions needed for specific soil and crop conditions. In addition to nitrogen, phosphorus and potassium, manure contains many secondary nutrients and micronutrients, as well as organic matter that helps build and maintain soil structure.
Research in Ontario done on perennial cool-season forages shows that manure applications can increase the yield of the crop over fertilizer alone when the rate of macronutrients (N, P and K) applied is the same from either source (Table 2-1).
| Yield (DM basis) | Quality | Yield + Quality (DM basis) | |||||||
| Treatment | tonnes/ha | Tons/acre | % change | Kg milk/tonne | Lb milk/ton | % change | Kg milk/ha | Lb milk/acre | % change |
| No added nutrients | 5.58 | 2.49 | – | 1,518 | 3,035 | – | 8,470 | 7,557 | – |
| Fertilizer | 5.72 | 2.55 | 2.4 | 1,535 | 3,069 | 1.1 | 8,772 | 7,826 | 3.4 |
| Splash plate | 5.92 | 2.64 | 5.7 | 1,519 | 3,038 | 0.1 | 8,989 | 8,020 | 5.8 |
| Surface band | 5.92 | 2.64 | 5.7 | 1,520 | 3,040 | 0.2 | 8,996 | 8,026 | 5.8 |
| Injected | 6.32 | 2.82 | 11.7 | 1,526 | 3,052 | 0.6 | 9,647 | 8,607 | 12.2 |