Caterpillar...Friend or Foe?

[stephanietx]

We've had quite a few of these guys pop up in our yard. They are feasting on my French Hollyhocks, Shasta Daisies, Mexican Petunias, and Million Bells. What are they and are they friend or foe?

(Click on pics to see larger)

From top:

Hosted on Fotki

Head-on Shot

Hosted on Fotki

On my Katie's Ruellia (sorry it's so blurry, but he was moving at a good clip!)

Hosted on Fotki

Thanks for your help!

[sandih]

Is the thing green or white? I can't tell by the photos.

[stephanietx]

His body is green with white fuzzies and black dots.

If you click on the pics you can see it larger. I just posted the thumbnails because I didn't want to use up too much bandwidth.

Stephanie

[sandih]

http://www.whatsthiscaterpillar.co.uk/america/hairy.htm

take a look at the fall webworm picture on the right side and tell me if that's it

[sandih]

To answer your basic question, if they are feasting on your plants, they are a FOE. I had a delimma last year on whether I wanted swallowtail caterpillars to eat my italian parsley or do I want them to be fat and healthy and become beautiful butterflies? I chose the butterfly route because I knew the parsley would come back, which it did. I raised 15 different caterpillars on that one pot of parsley last year alone.

In your case, you don't know what they are and they're destroying several things in your garden. I would remove them by hand and disgard them, put them in a tree somewhere or feed them to your koi if you have them.

[stephanietx]

Thank you Sandi!! I do believe you correctly identified this critter.

My DH has been destroying them as we find them and we've also just put out some trichogramma wasps. (I hope they don't drown with all this rain we're having!) This is the first year we've had caterpillars since we've moved in and this is our 3rd spring here.

Stephanie

[sandih]

I was lucky one year in finding a huge wad of the tent caterpillars as they were climbing up the trunk of my red oak. I hated to destroy the things until I found out what they were. They offer no benefits, so don't feel too bad.

[khwoz]

Keep in mind that the wasps only work before the worms (caterpillars) hatch. The trichogramma wasps attack the eggs of the worm, not the worm itself. If you have active worms eating the leaves, you need to use BT. In the future, use the wasps before the eggs of the worms hatch.

[sandih]

I think I read that you put the wasps out in March or April...before you know you have a tent caterpillar problem!

[Dirt Doctor]

Looks more like a moth larva, so it's a bad guy.

[P Ferrell]

Seems awfully simplistic to labels critters as "good guys" and "bad guys".
You may decide they're "undesirable" and get rid of them, but they're just
do'n what comes natural based on the cultural practices they encounter.

Regards,
Patrick Ferrell
Who never met an arthropod he didn't like, even the ones that stung him
Allen, Texas

[Dirt Doctor]

Good point.