The principle danger to crops from excess fertilizer placed too close to the seed corn comes from excess salts. In fertilizer, the nutrients that are of primary concern are N, K2O, and S. The combined amount of these three elements is used to evaluate the potential risks of a fertilizer rate and placement. To evaluate a particular situation, add the rate per acre of these three elements in the fertilizer, and refer to the table below.
Consult other sources when thinking of placing seed in close proximity of other crops such as soybeans, sugar beets, potatoes, small grains, etc.
|Maximum “Safe” Rate of N+K2O+S (lb./acre)|
|Fertilizer Location||CEC < 12||CEC > 12|
|0.25” to 0.5” away from the seed||8||15|
|1” to 2” away from the seed||15||40|
|More than 2” away from the seed||20||40|