Need your help. Is this good or bad?

Hi Everyone,

One of my apple trees has what looks like a spider web/silk net wrapped around the last 6 to 8 leaves on one branch. Those leaves have become brown and shriveled.

Inside there are "tons" of very tiny caterpillars moving around. I've attached two pics.  I don't want to ruin a good thing, but I also want to prevent a bad thing from happening before it's too late.  I don't know if these are just a bunch of caterpillars turning into future butterflies (good thing), or an angry horde of caterpillars that will consume my apple tree and all my hopes and dreams. That last part would be bad, to clarify.

Thanks in advance for your experienced guidance.

Brian

They look like tent caterpillars. They will denude your fruit tree. Spray them with baby oil or light vegetable oil. That will get rid of them.

Pests!  Because the caterpillars all return to the webbed nest, that is the time to clip the end of the branch and bag it for disposal. Some folks will burn it (carefully) in an outdoor fireplace to get rid of the caterpillars.  Left unchecked, they can do a lot of damage.

https://en.wikipedia.org/wiki/Fall_webworm
https://en.wikipedia.org/wiki/Tent_caterpillar

Burning Sage underneath them is supposed to work.

Phil Gardener wrote:Pests!  Because the caterpillars all return to the webbed nest, that is the time to clip the end of the branch and bag it for disposal. Some folks will burn it (carefully) in an outdoor fireplace to get rid of the caterpillars.  Left unchecked, they can do a lot of damage.

https://en.wikipedia.org/wiki/Fall_webworm
https://en.wikipedia.org/wiki/Tent_caterpillar

I found an email answer from Mike McGrath (Gardens Alive) that supported this idea here.

He also suggests using Bt-k (aka Bacillus thuringiensis - kurstaki) for the branches you can't prune and burn.  I think it would probably be a good way to generally keep the damage to your tree low -- I'm not sure how bad the infestation gets before you can notice these symptoms.  You can buy the product on Amazon or at many nurseries. We use this in our garden to reduce damage done by cabbage moth caterpillars and apply it every 2-3 days, as the moths aren't affected and will keep coming back from other peoples' gardens. I'm not sure what the re-infestation pattern is like with tent caterpillars.

n murray wrote:He also suggests using Bt-k (aka Bacillus thuringiensis - kurstaki) for the branches you can't prune and burn.  I think it would probably be a good way to generally keep the damage to your tree low -- I'm not sure how bad the infestation gets before you can notice these symptoms.  You can buy the product on Amazon or at many nurseries. We use this in our garden to reduce damage done by cabbage moth caterpillars and apply it every 2-3 days, as the moths aren't affected and will keep coming back from other peoples' gardens. I'm not sure what the re-infestation pattern is like with tent caterpillars.

They only have one or two cycles a year in most parts of the US, so unlike cabbage whites (which fly and lay eggs continually) once they are gone you should be fine for a while.

Thanks so much everyone! Very helpful.

It looks like you might have two different things going on.  The first picture looks like leaf-cutter.  They burrow under the surface of the leaf and leave their telltale tunnels behind.

That second picture looks like white fly.  

For leaf-cutter, I haven't found a solution, other than plant a diversity of other beneficial plants all around it and encourage the development of a community of beneficial insects that will eat them.  I used to get them bad on my citrus trees, but not so much at all anymore because there are so many spiders, ladybugs, wasps, preying mantus, etc.

For white fly, just blast the crap out of them with the garden hose.  Do it daily for a week or so until they've all been killed, dislodged, inconvenienced and have vacated the location.  I used to spray (way back in the day), but again, once you establish an environment where beneficial insects make their home, you don't want to do that.  I haven't sprayed in 14 years.  I haven't seen whitefly in 12.

1.  Plant a wide variety of stuff throughout your orchard.  Comfrey, veggies, flowers . . . the more species the better.  Let them go to seed and leave them throughout the winter.
2.  Don't keep things so clean that there isn't any place for insects to overwinter.  However, that does not apply to fallen fruit (where codling moths breed) or to suckers on the base of your apple trees (where white fungus will build up).
3.  Don't spray anything other than a garden hose.  Even organic all-natural sprays will kill the beneficial insects you are trying to encourage.
4.  When you eventually clean things up, do it a little bit at a time, and quickly replant new stuff so that there is always a broad diversity of stuff growing (or dying) throughout the garden/orchard.  If there is a way to clean things up but leave the pile of dead plant material laying over to the side, you'll still provide shelter and food.  I like the look of a clean garden, but I'm learning to pile stuff up and let it compost in place, rather than haul off everything, including the insect eggs that may be growing on the underside of dying plants.

Best of luck.

Parasitic wasps would help. A high diversity of plant life is the essential of attracting them. Some are extremely tiny.