It is estimated that there are 30,000 or more species of insects in Texas lawns, gardens, flower beds, trees and even homes. About 6,000 of these are beetles and 5,000 are moths and butterflies (so this means caterpillars). Even entomologists have not tracked down all species.
“Most people are prone to hate insects without good reason. In fact, most insects are beneficial or have no real impact on human lives.” From A Field Guide to Common Texas Insects by Bastiaan M. Drees, Ph.D. and John A. Jackman, Ph.D. Both are professors and extension entomologists in the Texas A & M University System.
It appears, like most things in life, the bad apples in the bunch give everyone else a bad name. Most homeowners see a bug in the garden and just want to kill it before identifying what it actually does in the garden. The lawn and garden has its own predator/prey dynamic. If you remove the food for the predator, then the system can be thrown off balance.
The key is to determine if it is a good or bad bug in your landscape. This can be hard because many times you may not see what is doing the damage. One story that has gone around the garden for years is about the gardener who came out to see their dill plant being eaten to the ground by a bunch of caterpillars. The gardener didn’t realize that the dill was host plant for the Black Swallowtail larvae (caterpillars). The gardener told a fellow gardener that they killed all of the hungry caterpillars. The fellow gardener told them that caterpillars will never kill the host plant. Needless to say, the first gardener planted two dill plants next year!
Back to identification. This can be hard or tricky, so there are several ways that you can find out who’s wearing the good guy hat and who’s the bad guy in the garden. The book mentioned above is a fast and easy read with great color plates in the center, as well as clear line drawings, and short, easy-to-read sections on the major insects. Some other good resources can be found on
https://www.texasinsects.org/, various Facebook pages (there are good groups on just caterpillars, butterflies, etc.), and websites dedicated to specific bugs like butterflies and moths. Catching a bug and placing it into a plastic bottle can help get a closer look. Phone cameras are excellent these days and a close-up can almost always be had.
Lady Beetle vs. Asian Beetle
Lady beetles, also called ladybugs and ladybird beetles, are probably the most recognized, beneficial bug in the garden. The six-spotted, little red/orange, round beetle has been featured in cartoons, children’s books, clothing, and even jewelry. The reason they are beloved is that this little bug is a fierce predator. It loves to eat hundreds of aphids, spider mites or mealy bugs in one meal! The soft, worm-like larvae sport gray and orange markings with rows of raised black spots. The larvae can out eat an adult and make excellent predators. But can you tell the difference between this sweetheart of the garden and the biting, invasive version, the Asian beetle?
The Asian beetle looks very similar, but is often a yellow or lighter red/orange than the lady beetle and has several more spots. Most of these beetles have a small, dark "M" or "W"-shaped marking on the whitish area behind the head. These beetles can bite and be aggressive, are harmful to dogs, invade your home, and leave behind a foul-smelling yellowish secretion that can stain walls and furniture. They're called Asian Lady Beetles because they were first introduced to North America in 1916 to combat aphids. But like kudzu, they're even more of a problem now because they have overtaken the native species, and our homes. They will swarm a house trying to invade it during the months of September through November.
For more information on the good bugs and bad bugs in your yard or garden, contact the Walker County Master Gardeners on Thursday mornings by calling the Walker County AgriLife office at 936-435-2426. We have an excellent brochure on butterflies that can be mailed upon request.
The Walker County Extension Office is also on Facebook. WalkerCoTxAgrilife has been established to provide updates and information to Walker County residents and landowners on a timely basis. The Walker County Master Gardeners are also on Facebook! Check out both of these Facebook pages and hit "like" to join.