May 2017 | Fly Parasites Offer Organic, Effective Fly Control
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Fly Parasites Offer Organic, Effective Fly Control

May 2017

Sustainable fly control uses beneficial insects to seek and kill immature flies. These beneficial insects are safe for humans and horses, and nearly invisible. IPM Laboratories produces fly parasites, tiny parasitic wasps that kill fly pupae before they can hatch into adult flies.

Often called beneficials, tiny parasitic wasps work day and night making food of fly pupae. As small as a gnat, the parasitic wasp deposits her own eggs inside the fly’s pupal case, killing the developing fly in the process. The developing wasp larva then feeds on the remains of the killed fly, pupates and turns into a new wasp adult. The young adult parasite chews its way out of the fly’s pupal case, mates and resumes the hunt for new fly pupae to kill. Parasitic wasps do not sting humans or animals, are nearly invisible and do not upset horses or humans. They remain on or near manure searching for fly pupae in which to lay their eggs.

Effective fly control minimizes egg laying and maggot growth, and keeps conditions favorable for the development of fly parasite populations. Keeping bedding dry and changing often, and keeping stables well ventilated will help reduce moisture and minimize the flies’ egg laying. Horse manure mixed with hay and urine is ideal for egg laying and larval development. A single female fly can lay at least 500 eggs, which continue to hatch even after the adults are dead.

Using biocontrol is easy – just sprinkle the parasites on and near manure piles, in stalls and near garbage compactors. Introduce parasites weekly or biweekly from approximately May 15 to October 1 in the northeastern US.

IPM Laboratories grows fly parasites suited to the eastern US climate and is the only producer of fly parasites east of Texas.

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