Handling Animal Manure for Crop Spreading Fly Control & IPM


Animal manure has become a valued soil amendment for improving cropland. This is primarily due to its organic content and key inorganic (NPK) nutrients to plants. Because of its ease of application, manure has been a staple of crop farming for years. And, due to continual animal production supplies can be found year round. It is common to field stack manure prior to spreading so that nutrients are applied when needed by the plants, rather than as they are produced. At times this may cause fly problems in the area. House, stable and other true flies (Diptera) can breed in these piles if moisture levels in the piles increase. Then as the manure is spread, flies can emerge from the manure and create a control issue. House flies (Muscidae) can venture more than a mile if conditions are right, so it is in the best interest of the farm to control flies.

To control flies a farm can employ an Integrated Pest Management (IPM) plan for the cropland. The IPM plan involves three important steps:

         Scouting: Looking for pests and signs of pest breeding (speck cards, digging in pile, fly ribbons on stakes). Scout manure that is being delivered to the farm.

         Control: Employing cultural and other methods of pest control to knock down numbers. Reducing manure moisture is key to fly control.

         Review: Periodically reviewing how well control is working and making adjustments


Common controls used in field stacks can include:

         Tarp piles within 10 days and compost pile covered for 14 days.

o    Compost fleece and plastic (black / clear) visqueen* are useful. These can be staked down to keep in place during storage of manure.

o    Windrow manure to help make covering easier.

         Use only dry manure kept in shelters prior to use.

         Apply a fly larva growth regulator (IGR) to the pile

         Spread the manure thinly in the field so to speed drying.

         Aerate the pile by scooping and restacking to enhance composing.

         Mix in organic matter so to speed composting. Straw, feed refusals, wood chips, bedding and other materials commonly found on the farm can be used as compost amendment.


Proper handling of manure stacks can keep flies from becoming a serious problem.

Poultry IPM Program

Gregory P. Martin, Ph.D., PAS Return to PSU Southeast Region Poultry Extension

Penn State University Extension

gpm10@psu.edu Return to PSU Extension

www.personal.psu.edu/gpm10 Rev: 9/2014


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