Alabama Pests: All About Catalpa Worms

Alabama’s insect population includes thousands of bugs. Some of them are common while others are completely unknown to the general population. One bug that many locals have seen before but know little about is the catalpa worm, which actually isn’t a worm at all.

Today, we’re giving catalpa worms the attention they deserve. Some people consider them to be yard pests, but catalpa worms are an important player in our ecosystem. Keep reading to learn more about why catalpa worms are in your yard and how to spot them.

Catalpa Worms a.k.a Catalpa Sphinx Moths

When someone references a catalpa worm what they are really talking about is a catalpa sphinx moth in the caterpillar phase. Catalpa worms also go by the name catawba worm.

Catalpa Worm Distribution and Habitat

Catalpa worms can be found throughout the entire eastern side of the U.S. from Texas to the Atlantic Ocean. They can live as far north as New York, but typically the population is concentrated in the southern states. In fact, there are two species of catalpa worms – northern catalpa and southern catalpa.

Catalpa sphinx caterpillars usually remain close to the catalpa trees that they feed on. Once the fall weather begins to set in catalpa worms will burrow down a few inches into the soil beneath catalpa trees to overwinter. If it’s a particularly warm fall catalpa worms can remain active around the trees until winter.

The Physical Features of a Catalpa Worm

A catalpa worm is easy to spot because of its high-contrast coloration. Newly hatched caterpillars are in what’s known as the pale phase. They are mostly white in color with spots of black down the spine.

Once they fully mature, the caterpillars have a solid black head and a wide strip of black down the entire back of the body. The sides and belly of a mature catalpa worm are bright, neon green to yellow in color. Catalpa worms also sometimes have a black horn at the rear end of their back.

Another physical feature of catalpa worms are their “feet”. As a catalpa worm moves tiny nubs protrude out from the bottom of its belly. They have a suction-like quality that grips to the surface to help catalpa worms crawl along.

One very distinctive physical feature for some unfortunate catalpa worms is a ridge of white wasp eggs along the back. Wasps are the catalpa worm’s biggest predator. The female wasps will attack catalpa worms and insert their eggs just under the skin. There the wasp larvae grow and begin to feed until they finally kill the catalpa worm.

Defining Behaviors of Catalpa Worms

It’s not just the unique look of catalpa worms that make them stand out. They also have a few defining characteristics and behaviors that set them apart from other summer insects.


The first round of catalpa worms hatch from their eggs around mid-May each year. Since catalpa sphinx moths lay 100-1,000 eggs at a time, it’s not uncommon for catalpa worms to suddenly appear in large numbers. After the initial emergence, there are usually 2-3 more generations born during the summer.


Catalpa worms got their name because of their feeding habits. They feed exclusively on the leaves of catalpa trees, which are native to the southern region of the U.S. Newly hatched catalpa worms feed together in groups. As they get older they begin striking out to feed on their own. Catalpa worms will strip the leaves baring, leaving behind only the largest veins and stubs.

Do you want to get rid of catalpa worms before they strip your trees bare? At Vulcan Termite and Pest Control Inc. we’ve helped countless Alabama homeowners control all sorts of insects with custom pest control treatments. Give us a call today to learn how we can help you get rid of catalpa worms and any other pests that are bugging you this summer.

Original Source: