Beesource Beekeeping Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
90 Posts
Discussion Starter · #1 ·
These horrible little monsters and another that looks similar but is black with long white hairs have been stripping my walnut and pecan trees BARE in the space of a week. Everything I read has a warning on it to NOT use around bees.
I have 24 walnut and 8 pecan trees I would love to see next year.
This is my first year with bees and im not sure how to kill these nasty things without killing everything, bees included.
Tangle foot work on caterpillars? They are definitely crawling up the trunks.
Something I can treat the ground with around the base of the trees?
I keep the grass mowed low under the trees and there isn't anything the need are using there but the hives are very near some of the trees.

 

·
Registered
Joined
·
2,944 Posts
once the tent caterpillers get into the web formation, BT won't penetrate to kill them. I have a few groups in my single pecan tree that I just let go. My neighbor didn't like them in his birch and he did use the tanglefoot this past winter and so far he doesn't have any in his trees.
 

·
Registered
Joined
·
93 Posts
Your trees will likely be fine. I've had mine be completely defoliated and they came back no worse for wear. They're tougher than you think. But if you want to do something anyway, just to make sure...

Yes, Bacillus thuringiensis, but the kurstaki strain. If the little buggers are still feeding, that will get them. I'd use Monterrey Bt if you can find it, or something else with the OMRI certification stamp on the label. Thuricide is good and the right strain, but I have no idea what the non-active ingredient is, the liquid the bacteria is floating in, so don't know about harm to bees. Plus, Thuricide is only 15% bacteria - Monterrey is 98% and works a LOT better in my experience.

If you can't find either, just look for something with the active ingredient Bacillus thuringiensis 'kurstaki' and the OMRI stamp. Both will be right there on the label.

It's a living thing, so keep it inside at room temp. And only mix up how much you're going to use right then. It dies 36 hours after mixing with water. Also, when you're buying it, make sure it's not out of date - call the 800 number on the label if you have to and ask the manufacturer, or buy it from a local garden center/nursery that gets a lot of business since it'll likely be fresh from them (not Home Depot or WalMart unless that's your only choice).

The tough part is you've got to cover all the leaves with it and on a tree of any size that's gonna' be tough. The caterpillars have to eat it, so it has to be sprayed all over everything so they will. And do it at dusk so the spray will take longer to dry out (when it dries out, it dies quicker). And, lastly, you might have to do it again a few days later, though if you spray thoroughly enough and the caterpillars are still feeding on the leaves, you should get enough of them that the tree can withstand the few that are left.

If you have any more questions, ask away! I do this for a living. I'm a horticulturist at a local organic-only garden center who sits at the info desk and answers questions just like this all day long.
 

·
Registered
Joined
·
90 Posts
Discussion Starter · #7 ·
Picked up a bottle of this at Tractor Supply. Ran out of daylight, but got about half of the trees sprayed as far up as the hand pump sprayer will reach. Tomorrow I will get the little pull behind 25 gal out, it shoots a good 20-25 ft high. That should get me most of the way up.
Found a garden center near me that carries the Monterrey. I can still here them eating, so the next treatment will be with the good stuff.

A few years ago it was drought, last year borers killed half a dozen walnut trees, this year they were bouncing back great...until I left for 4th of July vacation. Got back and panic time!
This is one of the worst.



Thanks for the quick response and all the help!
 

·
Registered
Joined
·
93 Posts
Oh. Dude. Wow. I'd be jumping to do something, too, with that history. A couple hard hits in as many years and that can definitely spell trouble.

You got some good stuff though. Garden Safe is a good brand. I went to their website and looked at the label info - 98+% Bt. That's VERY good. As good as the Monterrey. But changing up brands for the next treatment if needed is a good idea anyway.

Other than that, keep the tree as healthy and happy as possible. You may already know the following, but I can't help but say...

Get some liquid seaweed and drench the ground with it according to the package directions. It has plant stress hormones in it as well as lots of micronutrients. When a plant experiences an injury, it takes some time for it to make enough stress hormones, and it can't start healing until it gets enough stress hormones. Giving it seaweed will speed up that whole process.

Make sure they get enough water. If no rain in a month, throw a tuna can out there and use a sprinkler until it's full, then move the sprinkler and can around, and again, until the entire ground under the canopy has been covered. Don't be tempted to do more than that - they don't have many leaves, so won't be using near as much water as normal. They transpire moisture from the bottom of the leaves, mostly when they're making food, and leaves make food - so few leaves means little food making or transpiration.

If you want to go hog wild, you can spread a half inch of compost all under that tree canopy, too. Don't do much fertilizer if any - just the compost. Compost is like chicken soup when you have a cold, fertilizer would be like a chicken fried steak, mashed potatoes, gravy ... tasty, but not what you really need. (Btw, that seaweed? A hot toddy - bourbon, lemon, and honey. Mmmmm...).

And keep babying them for a year. They need all the help they can get to replenish the food stores in their roots. Those food stores down there are a lot like bees putting up enough honey for winter. They need that energy to put on new leaves in the spring. They'll use up some of them putting on new leaves now, then use a lot more next spring. They'll need all the help they can get next year to replace all that to the point they have a surplus again.

Good luck, man. I hope you don't lose them, but I don't think you will. I think they'll bounce back. I've seen ones in worse shape do it. That drought's done awful things to our trees, too, and I'm amazed at how many survived that looked as bad as yours. Yeah, they lost some of the outer portion of their limbs, but they were still there and are almost back all the way now.

Holler if you have any more questions.
 

·
Registered
Joined
·
3,112 Posts
tent caterpillars won't hurt your trees, they just look disgusting. The BT products should work fine, but even if you do spray them with bee-toxic pesticide, the bees don't forage on caterpillars, webs, pecan bark, or leaves, so it really wouldn't be a problem. Or you can do what I do. As soon as you see a big nest (tent) that is nice and full, take a propane torch to it. The silk is really flammable, and they will be burned alive. Get a lawn chair and a cooler of beer and make an evening of it. You kill the caterpillars and greatly reduce the moths that emerge and lay eggs for next year.
 

·
Registered
Joined
·
1,383 Posts
I have a couple of walnuts that they ravaged for several years. They never seem to do lasting harm to the trees even though they strip them clean of leaves. But killing those suckers is a good fun if not revenge. :thumbsup:
 

·
Registered
Joined
·
90 Posts
Discussion Starter · #11 ·
Been doing a spot treatment with a bernzo propane torch. And an occasional boot when a ball of them are low enough.
Thanks for the words of wisdom ******* hippie. I wrote most of the walnut trees off last year after the borers got into them. There are a few that died and a lot of dead limbs in some but im amazed how well they were bouncing back.
We are having a strange year, spring was a little dry and then rain started late. Its been great for the trees. Usually we would have multiple 100 degree days and dry weather July going into august. I think this is the coolest and wettest summer we've seen in years. I think this may be why the caterpillars have come on so strong.
The other benefit has been flowers are still blooming everywhere. I picked a good year to get started beekeeping. Its been easy on newly hived bees.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top