variable rate fertilization -Reply

JULIE ELFVING (ELFVING.JULIE@epamail.epa.gov)
Wed, 30 Aug 1995 09:45:09 -0400

Thanks, Karen. I know Randy and can easily get in touch with him. You
may also be aware that there is a precision farming demonstratino project
partially funded by us that is currentlly underway at Oran, MO on the
Bill Holmes farm. Jerry Carpenter, at MU-columbia would probably
have details if you want more information on that project.

>>> <dallasco@ext.missouri.edu> 08/29/95 05:11pm >>>
Julie,

Karen Ross here from Dallas Co., MO, Niangua Water Quality
Project.

I am unsure where variable rate fertilization stands now, but I know
that Iowa State University has done several research projects on it.
The last meeting I went to was in the summer of 1993 and at that time

it was shown to be an equal trade-off. There was no economic benefit

to variable rate fertilization since the cost of purchasing equipment
and additional testing was expensive, but there was a huge
environmental benefit since only the amount of fertilizer needed was
applied. It is important to note though that the natural fertility of
a soil varies a great deal even in a matter of several hundred feet.

I would suggest if you are interest in pursuing this further you get
in touch with Randy Killorn in Agriculture Extension at Iowa State
University. If he doesn't know he will be able to find out.

Karen Ross
Dallas Co
rossk@ext.missouri.edu