Fortunately for me, they seem to prefer our alder trees, which grow like weeds, so there is plenty to share. Some years are worse than others, and we haven't had a bad caterpillar year in a while, so it just may be time for a cycle. As destructive as they can be to the foliage, the trees generally survive, they just look awful. If I can reach the tents and catch them early, it is easy enough to just snip off the branch and burn them while the caterpillars are little and haven't traveled far from the nest.
