At the very least it can reduce yields on the first cut the next season. In a year like 1997 when the feed was really needed, the productivity of next years crop was not a high priority. We will have to manage around these decisions in 1998. Soil test results and forage value should be the basis for decisions on applications of phosphorus and potassium. With higher forage prices across the province, returns on dollars invested in fertilizer are that much higher than in the past.
Forages remove large amounts of nutrients particularly potassium.
Many fields do not get fertilized to the extent that is needed to maintain a productive stand. This is still a problem with many forage programs. Older fields with less legume and more grass content are not fertilized with appropriate nitrogen applications to boost yields and feed quality. Productivity of older stands may be boosted from lower production by proper fertilizer application. Ontario research on alfalfa by Dr. Bob Sheard in the mid 1980's found insecticide application consistently increased alfalfa yields each year.