bSo, back when I was reading about tomato hornworms at the beginning of July, I discovered that they usually (in our area, at least) have 2 hatchings. Awesome. Fast forward to a week or two ago, when we went down to the veggie garden...I had all but forgotten this news...until.....

See those black balls? They're slightly smaller than peppercorns. Tomato Hornworm frass, or droppings. (Not familiar with the term "frass"? We learned about it when reading up on Squash Vine Borers years ago) Uh-oh.

So I started searching for the little devils...I knew they had to be there. I knew they were hard to spot. Thing was, there wasn't really a lot of damage to the tomato plants. I was just thinking how strange that was when  I spotted the first one:

But hang on now. It had weird little white cylindrical thingies all over it...what the heck? And it wasn't moving...or...eating...could it be..?

Could it be one of these neat little parasitic wasps? Yep.. Sure enough. Those look like Cotesia congregata cocoons....parasitic braconid wasps.

Apparently, they lay their eggs in the larvae of hornworms, and cause viruses, which knock out its immune system...the hatched wasps live inside the hornworm until they emerge to form a cocoon (which is what those white things are)... The wasp larva disrupt the host's (hornworm's) endocrine system...and eventually, after the hornworms stop eating...

They die. Ah, the circle of life....and narry a scratch on our tomato plant this time around. Thanks, Mother Nature. Glad to have those little Cotesia congregatas around!


    Interesting. I found a hornworm about six weeks ago. Nothing since. Well, none that I know of.

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