A Plethora of Catepillars

All of the sudden we are seeing strange webs in the trees. But what could they be? Upon closer inspection they seem to be filled with something. And upon closer inspection we see that they are filled with catepillars. And upon even closer inspection we see that they are filled with lots and lots of catepillars. These guys are not environmentally friendly. They crawl out of the web and eat the tender new leaves until they are all gone and then the tree dies. Weird but interesting.