You know the old saying that goes, “Warm weather brings more bugs to the party.” No? Maybe that is because I just made it up, but that does not make it less true! The warm weather of May is bringing lots of bugs to the garden party!
Insect problems can be a frustrating part of gardening, especially when we can see the damage but cannot see the bug causing the damage! How can you fix a problem that you cannot see? One way to track down insect pests is to investigate
the damage from the insect. Some insects chew holes while others siphon plant juices out of the leaves.
Chewing damage is some of the easiest damage to spot. It’s hard to miss shotgun holes in leaves, half eaten leaves, or even a missing plant. I still have a hard time talking about the petunia massacre of 2018 when snails ate every single bit of my newly planted petunias overnight! Insects that chew leaves have a mouthpart with two opposing mandibles or jaws. Chewing insects cause ragged leaves, foliage consumption, or mining in the leaves, stems, or trunks. Caterpillars are often the culprit in the garden when you see chewing damage, but cockroaches, grasshoppers, most wasps, beetles, slugs, snails, termites, and pill bugs also chew on plants.
Other insects pierce the plant surface and siphon plant sap through a proboscis. The tiny holes are not visible, but the plant will show white, red, or brown spots where the sap was removed. Insects that pierce and suck include aphids, mealybugs, scales, squash bugs, leafhoppers, thrips, mites, and plant bugs like chinch bugs or stink bugs.
Some sucking insects inject a toxic secretion into the plant which further damages the plant. Chinch bugs are one example of this when they attack turfgrass and secrete a toxin that yellows and kills the grass. Aphids, scales, and mealybugs leave a sticky, sweet substance known as honeydew after they feed. A black mold called sooty mold grows on the honeydew, causing the leaves and branches to turn black. You might see this on crape myrtles and pecan trees in the late spring and summer.
If you see damage from insects in your lawn or garden, do some good investigation to determine which pest might be causing the problem. Once you know the particular pest, you can decide on a treatment plant. Aphids can be knocked off with a good blast from the water hose (check the bottom side of the leaves). Or you can pluck off caterpillars and drop them in a bucket of soapy water. A total infestation might require a stronger approach. Check out the Grow Green guides online to find out the least toxic methods to control your bug problems.
For more lawn and garden information, contact the Williamson County AgriLife Extension Office at 512-943-3300.
