1. On-Farm Nitrogen Fertilizer Demonstrations

The Magdoff Pre-Sidedress Nitrate Test (PSNT) has been successful 1y used in the Northeast and humid parts of Midwest to improve N fertilizer recommendations. A modified version of the Magdoff PSNT was evaluated in 1989 and 1990 in Michigan. Fifty-three large scale on-farm corn N demonstrations were carried out. Two rates of N (a reduced rate and a high rate) were rep1 icated 3 to 6 times in each field. Forty-six sites showed no significant (p=.05) yield reduction due to the reduce N rate. Forty-nine...