Inspecting plants helps identify pest problems early, before they get out of hand. Common plant pests in Louisiana include aphids, scales, whiteflies, thrips, plant-feeding mites, beetles and caterpillars. Detecting small insects and mites can be difficult; their entire life cycle can be as short as one week.

To detect small pests, strike the leaves of small branches against a sheet of white paper and use a 10-power (10X) magnifying glass to search for movement or evidence of pests, or use an optivisor (binocular headband magnifier) to check leaves and branches on the plant. Scales and whitefly larvae attach to the plant. Look for pests on branches and on both upper and lower surfaces of the leaves. Sooty mold on foliage often indicates an infestation of insects that pierce the plant and suck sap. “Piercing-sucking” insects often secrete a sugary substance known as honeydew, which serves as a medium for growth of the complex of several species of fungi. Sooty mold does not injure the plant directly, but it blocks sunlight from the leaves, reducing photosynthesis. Ants, bees and wasps signal the potential presence of pest insects. Ants tend these insects for the honeydew because of its high sugar content and food value. Bees use honeydew to produce honey, and wasps use the honeydew as well as some of the soft-bodied insects that produce it as a food source.

If you observe plant damage but few pests, beneficial insects may already be at your service. These may include lady beetles (ladybugs) and their larvae, lacewings and their larvae, syrphid fly larvae, praying mantids, assassin bugs, spiders, fire ants and parasitic wasps. Try to tolerate some insect damage and leaf disease on plants. No one can maintain an insect- and disease-free landscape, and a little damage won’t hurt your plants. Some pests are night feeders and are not observed during the day. When damage continues but no pests are observed during the day, check after dark to find potential pests. Remember, to have the “good guys” there must be some “bad guys” as a food source. If a pest problem persists, take a sample to your local county agent for identification and suggestions on how to precede using an integrated pest management program.