Update: We've Been Invaded

On April 7th, 2017 I wrote a blog post about being invaded by Forest Tent Caterpillars. It was called We’ve Been Invaded. The invasion was disgusting and fascinating all at once. The worms were everywhere for three yucky days then they just seemed to disappear. I didn’t know what had happened to them. I assumed that bats or birds or some other predator had eaten most of them, but I was wrong.

Each of the worms had found them a place that they thought was safe and spun themselves into a pale-yellow cocoon.

The worms are the larvae stage of this insect. While they are in the cocoon, they change into pupae, and then about ten days later they emerge as a buff colored moth. (The moth has already left this cocoon.)

The day I walked outside and discovered these moths all over the screens of my porch was the day I realized the worms hadn’t been eaten. But the moths weren’t too bad. They are nocturnal, and they only live a few days. Just long enough to lay eggs in the tops of the trees. Within three weeks after the eggs are laid the embryos will turn into larvae, and they will overwinter in the eggs and hatch in the spring when the cycle begins all over again.

We had a bad rainstorm during the few days the moths were alive. It will be interesting to see if that has any effect on their population levels next spring.

The worms almost stripped all the leaves off some of my older oak trees, but as you can see they are coming back. The top of the tree was damaged the most, after all, that’s where the moths lay their eggs. But a month ago all the branches looked as bare as the top one, so I’m hopeful my trees will be fine.

Being invaded by worms was disgusting for the three days that they were everywhere, but now that it is over and I can look back on the experience I’m thankful. We rush through life and don’t often get the chance to see the cycles of nature quite so dramatically. I think I will slow down a little more and see what else is out there.