Manure application is an alternative way
to add nutrients such as nitrogen and phosphorus to crops. Since livestock
operations can generate a large source of manure nutrients, it is important to
look for ways to reuse these nutrients for crop production and not just focus
on disposal. With effective manure nutrient application, farmers can reduce
their use of commercial fertilizers and save money. We want to recycle nutrients.
We want to be good stewards of the land so we don’t over apply nutrients. We
don’t want to have any runoff and we want to maximize our yields. We don’t
want to be out there when we’re compacting the ground and causing our
yields to go down, so we’d like to be sustainable. When it rains manure
nutrients can wash into nearby streams and rivers, and in Michigan, most streams
and rivers flow to the Great Lakes. When these nutrients enter our waterways,
the excess of nutrients can lead to plant and algae overgrowth, including
harmful algal blooms. These algal blooms can have a big impact on the Great Lakes
watershed. When decomposing, blooms consume oxygen fish and other aquatic
species need to live. Blooms can also affect the quality of drinking water and
can limit beach access. While there are other factors that contribute to harmful
algal blooms, farmers can help reduce nutrient runoff from entering the Great
Lakes through good timing of manure application. Since the timing is critical
farmers should consider the following factors: manure storage capacity, slope
and drainage of fields, weather forecasts and seasonal conditions, snow or water
saturation levels in fields soil temperature–especially frozen ground and
the type of manure being applied Keeping records of manure applications
can lead to a greater understanding of field dynamics and nutrient needs for
different cropping rotations. These records should include current soil test
results, manure nutrient analysis or book values and realistic yield goals–all of
which are important in planning the manure application rate. To help farmers
plan the best time for short-term manure application, Michigan State University
Extension and partners developed the Michigan EnviroImpact Decision
Support Tool. This online tool shows daily runoff risk across the state. Using
national weather service information about precipitation, soil moisture and
temperature and landscape characteristics. Visit the web site and
learn more about how the Michigan EnviroImpact Tool can help you save
money while protecting our Great Lakes.