By: Billy Skaggs, Hall County Extension Agent

Did you know that less than 3% of the insects commonly encountered in your landscape are actually harmful to the plants that we cultivate? Many are acting on our behalf as natural pest control agents. We can encourage their activity by learning to recognize which insects are beneficial and using practices that conserve natural enemies.

Conservation, or the protection of existing natural enemies may be accomplished by using management practices that minimize harmful effects. This includes using pesticides only when necessary and then spot spraying rather than spraying the entire landscape. Also, try to apply pesticides that are least toxic to beneficial insects when possible.

I suggest being very selective in applying broad-spectrum or persistent pesticides. Often natural enemies are even more susceptible to these types of pesticides than are the pests you are trying to control. Natural enemies may be immediately killed and toxic residues will reduce the beneficial insect population.

Planting a variety of flowering species can provide additional nectar sources and sources of alternative prey for insect predators and parasites. Nectar and pollen are required by many predators and parasites.

Well designed landscapes feature a variety of plant material including a season-long bloom of perennials. Those shown to be particularly attractive to beneficial insects include daisies, Queen Anne’s Lace, yarrow, white alyssum, goldenrod, and clover.

Introduction of beneficial insects may be considered when the current population is insufficient to reduce pest numbers to an acceptable level. In this case, natural enemy numbers can be increased through the purchase and release of commercially available beneficial insects.

Although this method has been widely used in the management of greenhouse pests, there has been relatively little research on the use of commercially produced beneficial insects in landscape settings.

Natural enemy releases are most likely to succeed in areas on plant materials where a certain amount of infestation and pest damage can be tolerated. Situations where high numbers of pests and a high degree of damage are already apparent are not good candidates for natural enemy releases.

A few such beneficial insects known to prey on other damaging insects include: spiders, stink bugs, assassin bugs, lace wings, parasitic wasps, predaceous damsel bugs and lady beetles.

For more information on beneficial insects, check out the Clemson Extension publication, Balancing Nature In Your Landscape, at http://hgic.clemson.edu/factsheets/hgic1722.htm

Beneficial ‘Bugs’ Contribute to a Healthy Garden