What is this on my tomato plant?

Asked August 1, 2014, 10:03 AM EDT

I found this in my garden on a tomato plant. Can you tell me what this is? It is some type of large caterpillar covered in eggs. Should I be concerned? I've never seen this before. Thank you-


1 Response

Thank you for contacting Delaware Cooperative Extension. You may receive a short survey after the answer to this question.
The picture shows a tomato hornworm with pupal cases of a parasite attached. The tomato hornworm is a caterpillar that is a serious pest of tomato, and will eat the foliage. Nature helps us out with this one, but means of a small wasp that is a parasite on the caterpillar. The braconid wasp lays its eggs on the caterpillar, the eggs hatch, the small wasp larvae feed on the insides of the caterpillar. As the wasps grow and develop, the caterpillar dies. By the time they are adults and ready to fly the caterpillar is done. So, although you may feel that it harms the caterpillar, it is nature's perfect biological control of this tomato pest. Of course not all caterpillars of the tomato hornworm get parasitized, so their populations are still around.

My best,