tomato hornworm


Parasitoid. A parasite that can kill its host. As in a Braconid wasp. A friend of the garden.

What does a destroying parasitoid look like? 

Here’s a guy in serious trouble. I found him this morning: 

 This tomato hornworm is riddled with larva that have eaten their way through the skin (from the inside out) to pupate. A wasp in the braconid family deposited eggs just beneath this caterpillar’s skin where the eggs developed until this point, dining away at the insides of the caterpillar. When the pupae are mature, and the adult wasps emerge, this caterpillar will die.

The possibility of having this beneficial wasp in the garden makes it worth keeping a few hornworms around…just in case this happens…

   Nature is pretty amazing!


Hi everybody. Sorry for the password protection. Seems a recent update had different default settings. Technology… rules us.

Speaking of protection……and now that I can share with you more images and idle chit-chat…..

Here is another critter that I had occasion to meet amongst my hot peppers. These guys are very pretty to look at, but boy howdy are they destructive. And….gooshy. Gross.

Anyway, here is a mighty eating machine I found on a jalapeno…

Tomato hornworm on a jalapeno pepper

Tomato hornworm on a jalapeno pepper

A pretty (and well fed) tomato hornworm. This particular ‘pillar likes plants in the solanaceae family. And because our tomatoes were long gone due to blight, this guy did just fine on a pepper plant, or two.

The caterpillar eventually will turn into a moth called the five-spotted hawkmoth (info sources: Wikipedia, Colorado State Extension). Hornworms are among the largest caterpillars. Because of their coloration, they are often hard to see (well protected/camouflaged on their host plant). The way you know they are there is the observation that your plant(s) had leaves yesterday, but it doesn’t today! The adults, however, are harmless. Hornworms transform into sphinx, hawk or hummingbird moths.

In terms of control, like with most bugs, the most recommended organic control involves manual removal (also read this to mean squishing them…yuck). Interestingly, these guys also have a natural control…there is a group of beneficial wasps (Braconid wasps) that parasitize these caterpillars by laying their eggs just under the pillar’s skin. As the eggs develop into larvae, the larvae eat the pillar from the inside out. Once the larvae migrate through the skin, they pupate along the back of the caterpillar, forming little white cocoons all over the ‘pillar’s exterior. The adult wasps emerge and the weakened hornworm eventually dies (

Interesting. Tragic. Nature. Glad I can share it all with you now.