My mother is experiencing a terrible outbreak at her lake home near Fergus Falls. Dropping off the trees, webs everywhere...nasty. Last week my wife and I observed a mini-outbreak on one branch of an aspen tree in Chester Bowl, black and clotted with writhing young caterpillars. We kept an eye on it for several days and the invasion did not spread beyond this single, tiny beachhead. Still, harbingers of things to come, I fear.