Well, the tent catepillars are killing all of our madrone trees. Last year there were only a few "tents" on some trees; this year, there is an epidemic of them.
We can't do anything aobut this because the webs are so strong, nothing penetrates them. Birds can't even get inside to the catepillars. Every week, more and more of the trees are encased. They even wrap around the trunks of the trees.
I noticed that these webs even stay from one year to the next, just shriveled from the weather.
Very sad. These are my favorite trees.