Gypsy Moths

[Knehrke]

It's no surprise I guess given the number of egg masses that appeared last fall and the hordes of dead moths that we needed to clean out of the tower blinds, but this year is shaping up to be a real winner. My wife and I noticed that nearly all of our small hardwood and fruit trees have small caterpillars on them, and the leaves are already showing signs of extensive damage.

How many of you have suffered through a gypsy moth scourge? I've heard that trees can become completely defoliated, but that they may generate a second flush after the caterpillars pupate. Have you experienced losses from gypsy moth? Or do most of the trees recover once the scourge has collapsed? Any idea of whether young trees are particularly susceptible, or the impact on hardwoods versus fruit trees? Frankly, it was tough walking through the property, wondering whether the thousands of hours over the past ten years is going to come unglued in a single season.

I'd consider spraying, but the volume of trees is prohibitive, and many are still in tubes, making it difficult to access the lower leaves. Additionally, the bacillus type sprays require that the moths to consume the bacteria-covered leaves in order to be effective. With the magnitude of this year's outbreak, I suspect that it wouldn't make a difference. And it's infeasible for me to spray once a week or after every rain. What to do? Maybe nothing, just pray.

 

[homerj1]

In many areas with thick infestations, state government will aerially spray Bt. Any chance of that happening where you are?

 

[Troubles Trees]

I found the same thing Knehrke, they were bad on my oaks and Chestnuts but not any on my Pears or Allegheny Chinkapin's which I thought was odd.

 

[Barndog56]

This is one of those deals where prevention is key. I always check my fruit trees for the egg masses while pruning, and then check again for the tents after they hatch. Of course I can't get the ones on the neighboring properties, so any caterpillars that make it through get squashed. I try to do an orchard walkthrough a couple times a week in the spring.

They have defoliated a couple of newly grafted trees in the past, but both survived and pushed new growth.

 

[Bill]

In many areas with thick infestations, state government will aerially spray Bt. Any chance of that happening where you are?

This^^^. I used to kick in with a neighbor in NJ to have about 60 acres combined sprayed for gypsy moths. If there are guys flying for the state they will also fly for private land owners. It wasn’t as expensive as you would think. My 30 acres was about $800.
That’s over 20 years ago so I’m sure it’s gone up....

 

[homerj1]

I always check my fruit trees for the egg masses while pruning, and then check again for the tents after they hatch.

No tents with gypsy moth caterpillars. https://fyi.extension.wisc.edu/gyps...masses by spraying,not labeled for gypsy moth.

 

[PatinPA]

PA sprays some state parks and state forest. I remember it being really bad in the 90's and 00's. Some years the mountainsides looked like the fall during the summer. Lately though I don't feel it's been very bad at all. Not that I noticed in my area anyway. I just looked up some info and they're calling for a bad gypsy moth year for 2021.

 

[Tap]

We had them bad back in the 1990s. My new home that I built has a wooded yard and we love the cool shade. I feared we would lose all of those trees so here was my approach.
I wrapped the trunks of 17 yard trees (south exposure of my home) with that sticky, 2 sided foil tape as a barrier. Gypsy moths sped the day in the tree and the night on the ground (so I was told). Each day the caterpillars would climb the trunk and stop at the barrier. There were often (LITERALLY) 1,000 clustered below the barrier! I would walk around each tree with a propane torch and cook each and every one of the little bastards. I know, without a doubt, that I was usually killing at least 17,000 per day (1,000 caterpillars x 17 trees), and it went on for weeks.
I guess the good news is that all of the remaining trees that I didn't band all survived. All of them were defoiliated but they all came back by the end of summer.
I think we had an infestation for about 4 or 5 years and then some sort of disease struck the moths and 99.9% died. I sill see an occasional gypsy each year but I rarely see an adult caterpillar or a moth. I pray to God that the disease sticks around and they dont become immune to it.
I cant tell you how much I despise them.
Another invasive from China. They make me sick.

 

[ProcraftMike]

We had it bad by us a number of years ago. It seems they are a bigger issue in drier years. They don't do well during wet years. The year we had it really bad, they defoliated every oak tree by us. I was convinced the trees would die. But, the trees leafed back out, like they do every spring. I suspect if that happened for a couple of years, the trees may not be able to handle the stress.

 

[jsasker007]

We had the worms come through but i don't recall seeing the moth stage, just the worms that seemed to border a biblical event. Seems they were around for a few years before they were done here. If you were in an area with a lot of trees you could stand still quietly and hear the worms eating leaves off the trees. awesome and devastating at the same time.

 

[Tap]

We had the worms come through but i don't recall seeing the moth stage, just the worms that seemed to border a biblical event. Seems they were around for a few years before they were done here. If you were in an area with a lot of trees you could stand still quietly and hear the worms eating leaves off the trees. awesome and devastating at the same time.

One fact about the moths...
The females are not capable of flight but the males can fly. Females just hang out on the trees and wait for males to find them and mate.
Females are much lighter in color than the males.

 

[Bill]

Different bug but my false
Horse chestnut has been defoliated every year.
I thought it was blight. Wrong. Just found it starting last week and found small mites.

waited til the flowers dropped and hit it with malathion today. We’ll see.

 

[Bill]

the bees love the flowers. So I wanted them to be done first.

 

[Knehrke]

Another invasive from China. They make me sick.

Not that there aren't a million Asian invasive species that are causing me daily headaches, but this isn't one of them. It was brought over from Europe in the 1880s by some guy who was attempting to breed a hearty silkworm. Insane. Much like Kudzu was brought in by the Corps of Engineers for erosion control or ornamental pears were planted along every driveway from Mississippi to Maine. We are truly our own worst enemies.

I may spray the high value fruit trees and keep fingers crossed on the rest.

 

[PatinPA]

We've also had real bad years with tent caterpillars too. They can strip a tree real quick as well.