Manure Spreaders are like a big wagon you tow behind a
tractor or other vehicle. Most manure spreaders use a belt
mechanism to break down and scatter manure and bedding.
Why it works. - Rather than stockpiling horse manure, you
shred it and use it immediately to fertilize your pastures.
How to do it. - First buy a manure spreader. You'll find
two mechanical options: PTO (power-take-off) or ground-driven.
PTO units require a tractor with a PTO hookup to run the
shred-and-spread machinery. They're more powerful-and
expensive-than their ground-driven cousins. Ground-driven units
distribute manure using a beater-driver that hits the ground as
the spreader rolls along, then flings out waste. Such spreaders
require no PTO, so can be towed by a garden tractor, truck, or
Advantage - No composting required, so your manure pile is
reduced whenever you hitch up the manure spreader. By dispersing
manure, straw, and shavings over pastures, you encourage the
waste to break down, while providing free fertilization.
(See Manure Management below on the problem of mixing wood
shavings with the manure).
Disadvantage - : If you don't have a pasture, you'll have
to locate a nearby, agreeable neighbor's on which to spread the
horse manure. If you choose to spread stuff on your own
pastures, beware: While composting manure generates heat that
kills equine parasites, merely shredding and spreading it
doesn't. As a result, you'll likely be reintroducing parasites
to grazing areas, so keep your horses on a regular deworming
program. (Tip: If you have cattle-owning neighbors, they'd
likely welcome your spreading efforts. Cattle aren't susceptible
to equine parasites, so contamination isn't a problem.)
Also, if your stall waste contains a high shavings-to-manure
ratio, you'll wind up with a carbon-to-nitrogen ratio that's too
high for your soil. In layman's terms, that means your pasture
will turn yellow. If you have shavings-rich waste, mix an extra
source of nitrogen, such as blood meal, bone meal, or straight
nitrogen fertilizer with the refuse before you spread it.
Managing horse manure in suburban
areas is often a problem because land, to properly store and
utilize the manure for crop production, is limited. In addition,
when horse manure is mixed with sawdust or wood chips, and
spread on farm fields with a manure spreader, it often stunts
crop growth. Since farmers don't want to stunt their crops, the
horse owner has few good options for disposing of manure.
Frequently, it is simply stacked outside until the pile gets so
big that a neighbor complains and the manure must be hauled to a
Why Does Horse Manure Stunt Crops?
Actually it doesn't; but sawdust or
wood shavings do. These wood products are the most common
bedding used for horses. When horse manure and sawdust (or
shavings) are put on soil the microorganisms in the soil start
to break them down. Unfortunately, these wood products have a
lot of carbon that the microorganisms use for energy but not
enough nitrogen to build protein. In other words, the
microorganisms have an unbalanced diet and they need nitrogen.
They find that nitrogen in the soil and they collect it more
efficiently than plants do. In fact, they do it so well that the
plants growing in the soil can't find enough nitrogen to grow
properly. That's called an "induced nitrogen deficiency" and it
The Nitrogen Enhancement System
The horse owner or the farmer can
add nitrogen fertilizer to the manure/sawdust mix or to the
soil. The added nitrogen can be used by the soil microorganisms
to break down the manure/sawdust mixture. Therefore, they won't
need to steal soil nitrogen from the growing crops. The
fertilizer should be added to the manure prior to spreading it
on the soil. Another option is to work the fertilizer into the
soil after the manure has been applied.
What Kind of Fertilizer and How
Use only ammonium nitrate
fertilizer with an analysis of 34-0-0 or ammonium sulfate with
an analysis of 21-0-0. Other types of fertilizers (especially
urea) can be lost into the air in a manure pile and do no good.
Add about 10 pounds of ammonium nitrate or ammonium sulfate per
ton of horse manure/sawdust mix. This is about 1/3 pound (about
1/2 cup) of ammonium nitrate or ammonium sulfate per 1,000-pound
horse per day.
Add the ammonium nitrate as the
stalls are cleaned. Simply pick a stall clean with a manure
fork, then add about 1/2 cup of ammonium nitrate or ammonium
sulfate (for a 1,000-pound horse) to the manure and bedding in
the wheelbarrow or spreader. Adjust the amount of ammonium
nitrate or ammonium sulfate if the horse is much smaller or
larger than 1,000 pounds. For example, only about 1/4 cup of
ammonium nitrate or ammonium sulfate per day would be needed for
a 500-pound pony. Apply the ammonium nitrate or ammonium sulfate
to the manure only after it has been removed from the stall.
After the ammonium nitrate or
ammonium sulfate has been added to the manure/sawdust mixture it
can be held in proper storage for several months without losing
the nitrogen. It can then be brought out of storage and spread
when the field and crop conditions are best. Manure should be
stored at least 50 feet from any drainage-way or water-course
and a grass filter strip should be used to limit runoff. Check
with your local Soil and Water Conservation District or the
Natural Resource Conservation Service for technical help on a
wide variety of resource management questions including manure
application, utilization and storage. In some cases, the state
or federal government may be willing to cost-share, with the
stable owner, on the construction of a manure storage structure.
The amount of horse manure/sawdust
that can be safely applied to a soil is based primarily on the
nutrient needs of the crop, the soil nutrient levels, and the
nutrient content of the manure/sawdust mixture.