An important aspect of nutrient management planning
is an accurate estimate of nutrient removal by crops.
Today’s crops may remove different amounts of nutrients
than those in the past because of new hybrids, yield levels
and nutrient management practices. The objective of this
project is to measure P and K removal by corn grain over a
range of growing conditions in the Northeast.
Across 13 sites in 5 states (DE, MA, MD, NJ, and PA)
of the northeast U.S., grain corn removal of P2O5 averaged
0.42 lb/bu with a CV of 24 percent. Removal of K2O
averaged 0.27 lb/bu with a CV of 17 percent. Corn yield
was significantly and positively correlated to concentration
of P, copper (Cu) and zinc (Zn) in the grain. Higher
yielding corn also tended to contain more K and Mg per
bushel. Further analysis will be done on 1999 corn
samples to confirm these findings.