Bay leaf problem

[pepperhead212]

A friend has a recurring problem with his bay plant, so I told him I'd post it here, to see if anyone has seen this. He lives in San Francisco, so it may be a spring bug out there:

"Each spring, when my bay trees put out their new leaves and try to grow up a bit, they get attacked by a small, green worm. This catepillar is around 1/4" to 1/2" inch long, translucent bright green, and forms little white webby cocoons around itself during the day, curling a leaf around to protect itself.

These worms are devastating my bay trees. They seem to only be able to eat the tender young leaves, but they eat all of those, preventing my bay trees from every growing.

What is this worm, and how do I fight it off? I've been googling hard to no avail."

Thanks for any help out there!

[Imp]

Originally Posted by pepperhead212

A friend has a recurring problem with his bay plant, so I told him I'd post it here, to see if anyone has seen this. He lives in San Francisco, so it may be a spring bug out there:

"Each spring, when my bay trees put out their new leaves and try to grow up a bit, they get attacked by a small, green worm. This catepillar is around 1/4" to 1/2" inch long, translucent bright green, and forms little white webby cocoons around itself during the day, curling a leaf around to protect itself.

These worms are devastating my bay trees. They seem to only be able to eat the tender young leaves, but they eat all of those, preventing my bay trees from every growing.

What is this worm, and how do I fight it off? I've been googling hard to no avail."

Thanks for any help out there!

He needs to contact his county ag agent. Take in a twig with one of the pests on it so they can ID it. They may be able to ID it over the phone.

[pepperhead212]

Thanks Imp...hopefully he hasn't tried this, and it is nearby him. I didn't even think of this obvious solution, and I even took a soil sample to mine this year!

[TXDirtDog]

Pepperhead, that description sounds like the Leaf Roller caterpillar that we have here. When out of control, they can take down a cucurbit plant pretty quick. They are named leaf roller because they eat a while, then curl over a leaf with webbing and form a small brown cocoon to change.

I solved the problems I had with them by spraying BT. Took 2 years of somewhat regular spraying to really knock down the recurring population, but I haven't seen any this year yet.

You might have him look up Leaf Roller.

Hope this helps.

[pepperhead212]

Thanks TX. I forwarded this to him, to see if it matches. I figured somebody would have seen this, even if I hadn't.

[TXDirtDog]

By the way, I went ahead and googled Leaf Roller caterpillar just to make sure I was steering you correctly on helping identify.

The widipedia hit gives 3 ways to control. BT, and 2 commercial types of insecticides including Sevin. Before I tried to become more organic, I first hit the various squash and cucumbers that were plagued by the leaf roller with Sevin dust. I saw NO benefit from the dust and I applied it heavily. Just thought I'd let you know in case this is what his critters turns out to be.