We're talking about livestock and poultry manure, and why it's critical to keep it at least incorporated or covered by cover crops. Regulations on winter manure applications vary by state. And a growing number of states now restrict or ban field applications between specified dates.
Gone are the days when nobody will care or notice what you do. So beware and prepare accordingly.
Climate change is also muddying the distinction between winter and spring. The Northeast and Mid-Atlantic are receiving earlier and more significant rainfall events.
"Winter manure application is probably the most sensitive nutrient management issue that farmers face," says Doug Beegle, Extension agronomist at Penn State University. "Many outside of agriculture feel that it should be completely banned.
"We all know that winter isn't the best time to apply manure. It should be our last choice. But on many farms, there are no other practical options," he concedes.
When spreading is a 'must do'
If winter or early spring manure applications are necessary, you must do the best possible job of applying this manure if you want to continue to have this as an option, cautions Beegle. Select the environmentally safest fields and timing of application to minimize loss potential and maximize nutrients that'll be available for crop uptake.
If you're from Pennsylvania, consider these winter manure application regulations:
* Spread only on fields with cover crops or at least a 25% residue cover.
* Stay as far away from water as practical – at least 100 feet from where water might flow during winter or early spring.
* Select the most level fields available; especially avoid significant slopes.
* Manure application is prohibited on slopes greater than 15%.
* Avoid spreading high rates of manure during winter. Unless you have an approved nutrient management plan, you can apply:
-- No more than 5,000 gallons per acre of liquid manure
-- No more than 20 ton per acre of dry non-poultry manure
-- No more than 3 tons per acre of poultry manure
* Avoid areas in fields were concentrated water flow is likely.
* Avoid spreading in poorly drained fields.
* Do not spread on snow unless it's unavoidable.
* Try to avoid spreading when rain or melting conditions are expected.
* Don't spread into roadside ditches or ditch banks.
* For daily spreading, mark where you stop spreading in case fresh snow covers the previous application to avoid skips and overlaps.
When it's officially winter
As noted above, from a regulatory viewpoint, winter depends on how your state defines it. In general, the farther north you are, the longer the ban on winter spreading. In Vermont, the winter ban ends April 1.
In Pennsylvania, winter is from December 15 through February 28; or anytime the ground is frozen at least 4 inches; or anytime the ground is snow-covered. And as Beegle points out, the above guidelines are still very applicable to early spring conditions.
Maryland nutrient management regulations prohibit spreading of commercial fertilizer and stackable manure between November 16 and February 28. The blackout dates will change for next winter.
Stackable manure must be stored in a structure or stacked according to specific temporary field stockpiling requirements if storage isn't available. Some nutrient management plans have specific situations where non-stackable manure can be applied during winter.
Maryland also has restrictions for fall application of organic nutrient sources. In that case, fallow ground must have cover crops.
If winter or early spring manure spreading may be a must, consult with a certified nutrient management specialist or seek assistance from your local Cooperative Extension. Do it beforehand, not after the fact.