Insect Allies

Insect resting on a stick. Photo credit: James Bailey

Part Two: Crowd Control

This is part two of a three-part series on beneficial insects — how to make them work for you in your garden or on your farm.

An abundance of predators like this nine-spotted lady beetle help keep aphid populations under control. Lady beetles feed exclusively on aphids and other soft body insects through their entire life cycle.

Insects are central to the functioning of ecosystems and play many important roles in our gardens and on our farms. These tiny animals with three body segments, six jointed legs, two antennae, two eyes and an exoskeleton, are found in almost every habitat — from forests to deserts to the highest mountains on earth. They walk, swim, hop, fly, hover and crawl on the ground, in the soil, on plants and in freshwater. There are millions of species of insects, and their benefits can be incredibly diverse.

But not all insects are beneficial, some are simply pests. In many cases, like when they take over your backyard barbeque, insect pests are merely an inconvenience. But they can become a more serious concern when they engage in activities like damaging crops or spreading vector-borne diseases among humans (e.g., West Nile Virus spread by mosquitoes and lime disease spread by ticks).

Thankfully, there are also thousands of insects that provide valuable pest control services, helping to thwart the spread of agricultural pests and vector-borne diseases.

The Champions of Pest Control

Dragonflies were some of the first winged insects to evolve, some 300 million years ago.

Dragonflies and damselflies such as this dot tailed whiteface love to eat flying insects like pesky mosquitoes which can be a carrier of vector-borne diseases.

Insects that provide pest control services generally fit into one of two categories: predators or parasitoids. Predators, like beetles, flies, spiders, mites and millipedes, attack and eat other insects.

Parasitoids, like wasps and flies, deposit eggs inside or on the body of a host insect. The larvae then feed on the host, killing it. Parasitoids are particularly beneficial to farmers when agricultural pests are their host species.

You can help protect and encourage these natural pest controllers by avoiding pesticides that kill them, and choosing native plants that provide them pollen, nectar and shelter.

Other Articles in this Series:

Part One: Decomposers on Duty
Part Two: Crowd Control (currently reading)
Part Three: The Fruits of Their Labour

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