Spend some quality time with your fertilizer spreader
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
Alerts. Check the label of any pesticide referenced to ensure your use is
included.
The
high cost of fertilizer this year has everyone looking for ways to use
it more efficiently and to use no more than necessary. One way to be
sure that you are getting the most for your fertilizer dollar is to
apply fertilizer as uniformly as possible. Many farmers in Michigan and
the Midwest still rely on various versions of the spinner spreader for
granular fertilizer applications. This year it is important not to
overlook the details. Such as, does the old spinner spreader apply
fertilizer uniformly? Or could it do better?
A fairly easy way to check the spread pattern is to lay out six to nine
or more greased boards in the field over the width of your intended
spread pattern, spread over them, and observe the distribution of
particles on the boards. If particle size and density of the fertilizer
material is uniform, then particle distribution should be uniform on the
boards across the spread pattern. Compare the outside, mid-points and
center of the intended spread pattern.
The boards need to be large enough to collect enough particles at your
application rate to be representative, 18-inches by 18-inches square
pieces of plywood work well. The grease on the board will make the
particles “stick” and not roll off the board. For most fertilizers such
as potash or urea, a thin layer of black grease will work. You may want
to use a different color of grease if using a dark-colored fertilizer,
such as some of the byproduct Ammonium sulfate products. Why not just
look at the ground? Crop debris, soil surface cracks, soil surface color
and clods can make it difficult to see and compare particle
distribution.
The most common spreading error encountered is improper overlap distance
where the driver is too close or too far away from the previous pass
resulting in strips of over or under application. Remember that
different fertilizers have different particle sizes and densities which
affect the rate of flow and distance of throw.
Other problems encountered include: improperly adjusted or worn fins on
the spinners; bent dividers on double spinner spreaders, making
application rates higher on one side of the spreader than the other; a
bent and or sprung frame holding the spinner(s) at an unintended angle
to the ground; and fluctuating rpm’s of the spinners, especially when
the machine is traveling up and down slopes.
As with all of your planting and application equipment, check drive
components such as bearings, chains and belts regularly to ensure smooth
and consistent operation. Lubricate according to the equipment
manufacturer’s recommendations and properly clean and store your
equipment at the end of the season.
For more information on troubleshooting the spread pattern and adjusting
your spreader, consult the manufacturer’s operator’s manual.
Editor’s note: For more advice about efficient fertilizer use, see our 2009 special issue at: http://www.ipm.msu.edu/fertilizer2009.htm