Have you been wondering what these webs in your trees are? They come from fall webworms, a pest similar to tent caterpillars (those demonic, hairy creepy crawlies that eat all the leaves off of trees in late May and June). It turns out that fall webworms are less harmful, though!
I did some research, and discovered some interesting facts about them, why they aren’t as harmful to trees as you might think, and how to get rid of them if you really don’t want them clogging up your tree branches.
About Fall Webworms
Like tent caterpillars, fall webworms enjoy eating the leaves off of trees after they hatch. However, they’re eating leaves at the end of the season, when the leaves have already done their job and are dying off anyway. The trees are generally unharmed and will grow back just fine next year. Of course, if you have a very small tree or really hate the look of the webs, it could still be a problem.
In addition to appearing later in the year, another way fall webworms differ from tent caterpillars is that their nests appear at the end of branches and encompass the leaves there, rather than near the base of branches like tent caterpillars.
Fall webworms have a unique life cycle. They emerge from their eggs and begin webbing immediately, which they expand to include more leaves as they grow. They can go through 11 growth stages before pupating in old leaves, soil, or bark for the winter. The next spring and summer, they emerge and begin laying eggs to begin the process again.
They are not picky eaters. You can find fall webworms in over 90 species of deciduous trees!
In case you’re wondering, full-grown moths are almost fully white up here when we see them. Further south, they have more brown spots.
How to Deal with the Webs
So, what can you do about them? Well, like tent caterpillar nests, you can cut the affected branches from the tree and set them on fire. Always a good time, but if you don’t want to worry about accidentally starting a backyard tent inferno, there are better options.
The simplest option is to just leave it if it doesn’t bother you. Chances are, the fall webworms aren’t harming your tree, so aside from not liking the look of it, there’s not too much reason to dislike them. The webs will turn brown once the caterpillars go into their pupa stage, and will fall out of the tree altogether from the wind and snow of winter.
If you want it gone pronto, you can remove it pretty easily yourself. Just like spider webs, you can grab a stick and make caterpillar cotton candy out of it. After you’ve gotten all the webbing and webworms out of the tree, you can make an offering out of it for the birds. The birds are big fans, in fact, there’s one out pecking at a web in our apple tree as I write this.
If you don’t want to wait for birds, you can dump your fuzzy stick in a bucket of soapy water.
It’s not a good idea to try using pesticides on them. Apparently, the web won’t let pesticides through to kill them, and the other methods are more effective.
Hopefully, you can now make an informed decision on how to deal with fall webworms! If you’d like to learn more scientific facts about them, check out this article.
These caterpillars are interesting, but not a lot of fun… but Monarch caterpillars are! Here’s how to raise them.