Question:

How do I get rid of these worms and tents in my trees? (see photo below)

Answer:

At this time of year, I have also seen the presence of fall webworms, especially at the tips of tree branches. Fall webworms construct these nests (aka silk tents or webs) and the caterpillars feed within the nest. DO NOT PANIC. Fall webworms are native insects.

The defoliation and presence of large webs is not attractive, but this damage is generally not significant on healthy, well-established trees. Fall webworms are rarely numerous enough to completely defoliate trees.  By the time the leaves are being eaten, trees have already stored enough energy for their survival so fall webworms’ impact on trees is usually pretty minimal. There is no need to intervene. Wind and rain will usually eliminate webs over time.

While fall webworms might look similar to other tree pests, their impact is much different than the threat posed by spring caterpillars, such as the eastern tent caterpillar, forest tent caterpillar or spongy moth. Because these emerge in the spring, they can cause more damage to trees as the caterpillars eat the newly emerged leaves. Another difference: Forest tent caterpillars build smaller, flat silk mats, not large webs; spongy moth caterpillars do not create webs at all.

Do NOT attempt to burn the webs off. This will cause more harm to the tree. If you absolutely need to remove the nests, carefully prune out the nest – only if pruning will not affect the health of the tree.

Learn more:

https://hort.extension.wisc.edu/…/fall-webworm…

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You can reach Julie, your local horticulture educator by calling 262-741-4958, Text 262-374-4191, email julie.hill@wisc.edu or use our online form: go.wisc.edu/PlantQ