August 18, 2021 - Tomato hornworms are not hummingbird moths

Tomato hornworm

 OK- here's a rant. I am seeing this on various social media sites constantly and it's making me frustrated. It seems people are now into "rescuing" tomato hornworms because they are under the mistaken assumption that they turn into "hummingbird moths". This FALSE information is everywhere and people keep blindly sharing it.

Tomato and tobacco hornworms are closely related and both eat tomato plants. They are those big fat green worms with a "horn" on the butt. Their scientific names are Manduca sexta ( tobacco, most common) and Manduca quinquemaculata ( tomato). When they finish devouring your tomatoes they drop to the ground and make a chrysalis in the soil. They mature into a big gray moth called a hawkmoth, NOT A HUMMINGBIRD MOTH.

There are several species of hummingbird moths, those little day flying moths that can hover and look somewhat like a hummingbird. The most common one is the White Lined Sphinx moth -Hyles lineata. Their caterpillars do not eat tomato plants, but feed on a variety of plants like apples, grapes, peonies and four o clocks. Some species have a little horn but the caterpillars are smaller and do not look like hornworms. They are what turns into the moth that looks like a hummingbird and is often called the hummingbird moth.

Let me repeat this - TOMATO HORNWORMS DO NOT TURN INTO HUMMINGBIRD MOTHS!

So do not rescue tomato/tobacco hornworms. Squish them. Each one of them will make a whole lot more hornworms. They are not what we consider a beneficial insect.

This is what the tomato hornworm turns into. This is a Manducta or hornworm adult moth.

Photo credit Mark Dreiling Bugwood.org