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57 Ways To Protect Your Home Environment (and Yourself)
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12. Conserve Beneficial Insects

Pictured is a lady beetle larva.

Some bugs are on the side of homeowners. They are the natural enemies of damaging insects and are known as beneficial insects. Releasing beneficial insects into your yard or garden may have some benefit, but your best bet is to conserve the beneficials already there. Keeping beneficial insects alive may help keep pest problems at an acceptable level so you can reduce insecticide use.

To conserve beneficial insects, you first need to know how to identify them. Presented here are some common beneficial insects.

Pictured are green lacewings eating aphids.

Pictured are green lacewings eating aphids.
Pictured is a praying mantis.

Pictured is a praying mantis.
Pictured are wasp eggs on tobacco hornworm.

Pictured are wasp eggs on tobacco hornworm.
Pictured is a syrphid fly.

Pictured is a syrphid fly.
damsel bug

An important way to conserve beneficials is to treat yards and gardens with insecticides only when pest populations are great enough to cause significant damage. Many insecticides are nonspecific, which means they kill all insects, including the ones you want to keep. In addition, use the most accurate application methods you can.
grasshopper

Although most insecticides are not selective enough to kill only the particular insect you have targeted, shop carefully to find one that is more specifically aimed at your pest problem. Insecticides that must be applied directly to the insect or that break down quickly on treated surfaces kill fewer beneficial insects.
ambush bugs

Beneficial insects are often slow to colonize a yard. The best way to make sure they are nearby is to maintain their natural habitats. You can do this by maintaining a diversity of plantings.
queen anne's lace

Adults of some beneficial insects need to feed on pollen and nectar. Plants with very small flowers and some flowering weeds, such as some clovers and Queen Anne’s lace, in and around the yard may help preserve a diversity of insect life. In addition, artificial food supplements that contain yeast, whey proteins, and sugars can attract or increase the numbers of beneficial insects.
aphids

Keep in mind that maintaining habitats and providing artificial food can attract pests as well as beneficial insects. Also, although it is important to bring pest populations below damaging levels, it is not necessary to completely eradicate undesirable insects. In fact, leaving some pests alive will help maintain the populations of beneficial insects.
lady beetles

In many cases, conserving beneficial insects will provide natural control of insect pests. But natural control does have its limitations. Predators and parasites work slowly. It may take weeks or even seasons for beneficial insect populations to build up. Also, you are always left with at least a few undesirable insects in the yard.
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