Summary Once the crop is established, the fertility program will focus on maintenance of good fertility levels in the soil for the life of the forage stand. The most important part of the maintenance program is regular soil testing to determine the need for lime, phosphorus, or potassium to replace the large amount of nutrients removed in the forage. On grasses, nitrogen will also be an important part of the maintenance fertility program. Manure is best applied to corn. It can also be effectively used on grass forage, but it is not as well suited to use on legumes.
Micronutrient deficiencies are rare in Pennsylvania.
There may be a few situations where sulfur or especially boron may be required. Plant analysis, when properly used, is an excellent tool for improving the fertility management of perennial forage crops.