Project Details:

Soil available phosphorus (P) can vary considerably within a field. The current practice of applying one fertilizer rate to an entire field may result in over fertilization of some areas and under fertilization of others. However, the short range variability of soil test P may make site specific management of P economically unfeasible due to the costs associated with characterizing the spatial variation in soil P.

The use of seed-placed fertilizer on corn has become an established practice in southern Ontario. Many experiments have been conducted using this practice most of which have resulted in yield increases and frequently at soil test levels above those at which a response would be expected with a side-band fertilizer application 5 cm to the side of and 5 cm below the seed. Response of corn to seed-placed P have been compared to a side-banded P application in a few experiments. These experiments did not have the scope to determine if seed-placed P can replace the need for side-banded P (or at least at what soil test levels can it replace side-banded P), or if the response of seed-placed P additive to the response of side-banded P.