Beneficial Insects and Arthropods For Insect Control in Lilies

Quick Facts…

Beneficial arthropods can prevent or limit pest problems in the yard and garden.  These “friends” can be categorized broadly as either insect predators or parasites.

Predators include lady beetles, lacewings, spiders, and preying mantis.

Common insect parasites are the tachinid flies, the braconid and the ichneumonid wasps. When insecticides are needed, choose ones that are selective and less likely to harm insect predators and parasites.

Most insects and other arthropods found in the yard and garden do not feed on or harm plants. Many of these are just passing through or have innocuous habits. Others feed on and destroy pest species. In many cases, the activities of these beneficial species can completely prevent or greatly limit pest problems. It is important to recognize these beneficial arthropods so they may be appreciated and conserved.

Beneficial arthropods are categorized broadly as either predators or parasites. Adult or immature stages of insect predators, or both, actively search out and eat prey insects. Predators include lady beetles, lacewings and spiders. Insect parasites develop in or on a single host from eggs or larvae deposited by the adult parasite. Common insect parasites are tachinid flies and the braconid and ichneumonid wasps.

Insect Predators

Lady Beetles

Often called ladybugs, lady beetles are the most familiar insect predator. Most adult lady beetles are round to oval, brightly colored and often spotted. The immature or larvae stages, however, look very different and often are overlooked or misidentified. Lady beetle larvae are elongated, usually dark colored, and flecked with orange or yellow. Adult and larvae feed on large numbers of small, soft-bodied insects such as aphids. One group of small, black lady beetles (Stethorus) is important in controlling spider mites and others specialize in scale insects. Lady beetles can rapidly control many developing insect problems, particularly if temperatures are warm.

One species of lady beetle, however, the Mexican bean beetle, is a plant pest. This common Colorado insect is found feeding on bean leaves. It is distinguished from other lady beetles by spotting and color in the adult stage. Larvae of the Mexican bean beetle are yellow and spiny.