FOBs Melissa and Bill Cox write in, “What is This?”
Hi Melissa and Bill,
You have a Tomato Hornworm, which is a a hawk moth member of the family Sphingidae. They have a voracious appetite and will completely defoliate your plant, including stems and immature fruit. Tomato Hornworms are fond of many members of the family Solanaceae, which includes moonflower, morning glory, pepper, eggplant, tobacco, and potato.
The caterpillar is probably ruining your plant but if you wanted to see it go through its life cycle, you could place the caterpillar in a terrarium and feed it the foliage of the plant that you found it munching on. Alternatively, the easiest way to kill the caterpillar is to drop it in a dish of soapy water.
Tomato Hornworm covered with Beneficial Cocoons of the Braconid Wasps
Thanks Jennifer for the comment (see below).
Good Morning Gloucester 
Just don’t kill the tomato hornworm if it has tiny, little white things sticking out of it. Those are eggs for a wasp that when they hatch they kill the hornworm and go on to make many more “good wasps.” If you see one with these eggs, pick it off your tomato and just throw it in weeds somewhere else. It’s not smart enought to climb back to your plant.
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Thank you Jennifer for for adding this bit of good information–I was planning to, but just ran out of time.
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Thank you for this bit of info, we just found one on our tomato plant.
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You are welcome Stu–I think we have all had them at one time or another!
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EWWWWWWWWWWWWWWWWWWWWWWWWW
Thanks for the information!
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Welcome Melissa–your comment says it all!
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I found small black scat on the leaves and munched foliage but cannot find the worm? Any tricks?
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