gray fly

Say goodbye to all those pesky flies around your barn.

Flies and mosquitoes are two common pests found around the barn and pastures. Did you know you can control them using natural methods that are also affordable?


Don’t wait to deal with pesky flies after they’ve grow into egg-laying, disease-carrying adults. Put an end to flies while they’re still babies. How? By using parasitic wasps, which dine on fly babies.

Here’s how the process works
• Flies. The adult female fly lays her eggs on horse manure. The eggs grow into larvae (the maggot stage) and burrow into the manure. The larvae then grow into pupae (the cocoon stage). If left to continue maturing, the pupae grow into adult flies. It takes less than two weeks for a fly to mature from egg to adult.

• Parasitic wasps. The adult parasitic wasp deposits her eggs inside fly pupae. As the wasps mature, they eat the fly pupae, killing them. The parasitic wasps, being well-nourished from the fly pupae, grow into harmless, gnat-sized adult parasitic wasps. It takes two to three weeks for a parasitic wasp to mature from egg to adult.

The parasitic wasps can be purchased from natural pest-control companies. The wasps are shipped every three to four weeks during the fly season, which extends from spring through fall. When you get a shipment, you simply disperse small handfuls around your property in areas where there are apt to be fly eggs. These areas include in manure piles, under water troughs, below bedding, at feeding locations, and around the corners of pens and paddocks.


Mosquitoes are not just blood-sucking bugs with annoyingly high-pitched buzzing sounds. They carry the potentially-deadly West Nile Virus!

You can kill mosquitoes using pesticides. However, pesticides usually kill only adult mosquitoes. Another way is to kill mosquitoes at the baby stage, long before they have a need to ingest blood. You can do this by using a type of bacteria called Bacillus thuringiensis ssp. israelensis. It’s called “Bti” for short.

Here’s how the process works
• Mosquitoes. The female mosquito typically lays her eggs, either singly or in groups called rafts, on the surface of standing water. The standing water can be in such places as ponds, puddles, ditches, water troughs, tree holes, swimming pools, bird baths, old tires, and flower pots. The eggs hatch into larvae within a few days. Some species of mosquitoes lay their eggs on the ground in flood-prone areas, and these eggs hatch into larvae when the water appears–sometimes up to two years after the eggs were first laid.

Mosquito larvae, called wigglers or wrigglers, live in water, feeding on tiny organisms and organic matter. As the larvae mature and grow, they molt or shed their skin four different times until they turn into pupae. The four different moltings are referred to as instars.

The pupae, called tumblers, also live in water. During this stage, which is similar to the cocoon stage of the butterfly, the pupae rest and don’t eat. But the pupae can swish their tails and tumble about in the water to escape predators. In about a week they emerge as adult mosquitoes.

The adult mosquito rests for a short period of time on the water or other surface, waiting for its body parts to harden and its wings to unfurl. Adult mosquitoes feed on plants for nourishment.
Males and females mate shortly after emerging as adults. The female bites humans, horses, and other animals in order to get protein-rich blood to nourish her eggs. Males live only a few weeks, while most females live up to a month and can have several batches of eggs. Some species of females live longer and survive through a winter.

• Bti. Bti is a special type of bacteria that infects and kills mosquito larvae. When the larvae eat the Bti, it damages the gut cells of the larvae, quickly paralyzing and killing them. Bti can reduce the mosquito larvae population by half in just 15 minutes, and the rest in about an hour.

Bti, which can be purchased from natural pest-control companies, comes in granule or donut-shaped form (called “dunks”). Bti is applied to the ground or in the water where mosquito eggs are apt to be. The particular formulation of Bti that is used is highly-selective, only killing mosquitoes, and their close relatives, including gnats and black flies. It does not kill other kinds of insects, nor does it kill fish, birds, worms, and mammals.


There are a number of companies that sell natural pest control products, including parasitic wasps and Bti.

One company selling wasp parasites and Bti is Arbico Organics. For 30 years, the company has been producing and supplying commercial growers, landscapers, ranchers, pet owners, and home gardeners with natural pest control products. It is Arbico’s mission to provide its customers with the highest service, finest-quality products, excellence in product education, and integrity towards leadership in the organic industry. Arbico Organics has reduced its prices to make its products even more affordable during the current economy. Visit