odor and aesthetic problems
With a little advance planning and a minimal investment, these problems
can be reduced or eliminated.
Managing to Reduce Litter Production
A partial cleanout between flocks that
removes only caked material will substantially reduce the volume of litter
that has to be handled, compared to a complete cleanout each time. Once-a-year
total cleanouts are adequate for good production and may allow timing close
to when the litter can be used. However, in some cases, more frequent complete
cleanouts may be necessary to deal with specific problems such as diseases.
Good management of the drinking water
system is the best way to reduce the amount of caked litter that must be
removed between flocks. Closed system drinkers are the most efficient method
of reducing cake production. Careful attention and regular nipple replacement
will save water, improve production and reduce ammonia and the amount of
caked litter formed.
Direct Application to Fields
The most efficient method of handling
poultry litter is to directly apply it to fields as it is being removed
from the house. This reduces labor, expense and potential environmental
problems. This requires cleanout when weather and crop conditions are favorable
for applying litter. For cropland, this time will be in the spring before
the crop is planted, or in the fall after the crop has been harvested if
a small grain or cover crop is to be planted. Application of poultry litter
to cropland during the winter should be avoided because the efficient use
of nutrients will be low and the potential for water contamination is increased.
Pasture and hay crops such as tall
fescue and other grasses offer more times during the year for applying
poultry litter. Grasses are efficient users of nitrogen and respond well
to applications of poultry litter. In the case of fescue and other cool
season grasses, poultry litter can be safely applied from March to November.
However, it is recommended that no more than four tons per acre be used
each year due to potential livestock problems.
Summer annual grasses such as millet
and sudangrass can benefit from applications of poultry litter about anytime
between April and September. Poultry litter can also be used with wheat
and other small grains either before planting in the fall or as a spring
topdressing.
Good Litter Management Practices
Apply poultry litter in amounts needed
to supply the nutrient needs of the crop to be grown. Have soil samples
from the fields that are to have litter applied tested to obtain lime and
nutrient recommendations for the crops to be grown. Also, send a representative
litter sample to a laboratory for analysis. See Extension publications
AGR-146 and 146A for more details on how to calculate the amounts of litter
that should be applied.
When Storage is Necessary
When litter is to be stored, there
are several acceptable methods to consider. An easy, but unacceptable,
method is simply just to pile it outside the house. These exposed piles
can result in runoff, which causes nutrient loss and environmental problems.
These problems can be prevented with just a little thought and effort,
considering the following points.
Stacking: Proper stacking of
poultry litter will minimize problems with nutrient loss and potential
environmental contamination. Choose a well-drained site that will be convenient
to get to, but will not drain directly into streams or other areas such
as sinkholes where it might cause problems. Position the length of the
stack up and down the slope to prevent water from collecting behind it.
Stacks should be uniformly shaped with steep sides and a well-rounded top.
Stacks formed in this manner will shed water and be less likely to lose
nutrients and will provide sufficient heating to reduce potential disease-causing
organisms.
Plastic Covers: Stacked litter
can be further protected by covering it with plastic. It is not as important
to compact the litter; however, the rounded top and steep sides of the
stack are important. A windbreak of some sort near the stack could help
prevent damage to the plastic. Use heavy-gauge (6 mil) plastic sheeting,
anchor it to prevent wind damage and take care not to tear holes during
application. Anchor the plastic at the edge of the stack by placing it
in a small trench and backfilling with soil. Old tires and rope placed
over the plastic can be used to reduce wind damage. See Figure
1.
Concrete Slab Stack Pad
Some producers may already have or
wish to construct a concrete slab for use in stacking poultry litter. This
can further reduce the chances of nutrient loss and water contamination.
However, its greatest advantage may be in convenience to the producer.
In constructing a concrete slab, plan on using six inches of concrete on
top of a compacted layer of gravel or crushed rock that is at least six
inches deep. Footers should be formed along the edges that are at least
12 inches deep to add strength. Wire mesh reinforcement will also add strength
to the pad. A good gravel or crushed rock roadway leading to the pad will
allow access when the ground is wet and soft.
The litter should be stacked as discussed
previously. More litter can be stacked on the pad if it is well-compacted
as the stack is built. If a plastic cover is to be used, heavy wooden boards
or concrete blocks can be used to hold down the edges. See Figure
2.
Concrete Bunkers
Above- or below-ground concrete bunkers
such as those used for making silage can be used for storage of poultry
litter. The walls will allow a higher and more compact stack than can be
achieved on a concrete slab. This results in a smaller surface of the litter
being exposed to the air and weather, thus reducing the chance of nutrient
losses. As with the other types of stacks, a plastic cover can be used
to keep water out.
Roofed Structures
Structures with permanent roofs can
be used for storing poultry litter and are very effective in protecting
it from the elements. However, they have several disadvantages. First,
they are more expensive to build and maintain as compared to the other
alternatives. Any metal parts, such as roofs, are subject to rapid corrosion.
The roof may limit access by equipment and limit compaction of the litter
as it is stacked. A covered structure will likely be used by wild birds
that may transmit avian diseases.
In building a roofed structure, the
floor and walls that will be in contact with poultry litter should be constructed
of concrete. When litter comes in contact with wood or other combustible
material, a fire is possible as the litter heats soon after stacking. Be
sure the roof is high enough to allow access by equipment for stacking
and loading. If the roof is 12 feet or higher, walls may be needed to prevent
rain from blowing in. See Figure 3.
Caution
Poultry litter heats through microbial
activity during the first few weeks after it is stacked. Temperatures of
150° to 200°F are not unusual. When manure or litter from different
sources and/or moisture contents are stored together, or if the moisture
content is over 25 to 30%, temperatures can go higher, and spontaneous
combustion may occur. Do not stack wet litter in contact with dry litter.
Monitor temperatures of stacked litter daily for a week or two after stacking
to detect overheating. Stacked litter should not be applied to growing
crops until the internal stack temperature is 100°F or less.
Nutrient content of stacked litter
is usually quite different from fresh litter. Stacked litter should be
sampled and tested at least two weeks after stacking and as close to the
time of application as possible.
Summary
With prior planning and good management,
the nutrient value of litter can be preserved and contamination of surface
and ground water can be prevented with a minimum of added expense. More
elaborate systems are available that are effective and convenient as well
as more expensive. Producers should choose what fits best in their situation
and protects the environment.
For more information on storage structures
see your local Cooperative Extension Service office or Natural Resources
Conservation office.
The author acknowledges the contributions
of Fact Sheet 416 by H.L. Brodie, L.E. Carr, C.F. Miller, Structures for
Broiler Litter Manure Storage, Cooperative Extension Service University
of Maryland System, 1990. Appreciation is also expressed to the Cooperative
Extension Services in Alabama, Arkansas, Georgia, North Carolina and Virginia
for providing information for this publication.
This publication is partially funded
by the Tennessee Valley Authority.
