You will probably see them the next few years as they migrate south and west, They were in my neighbors crab apple tree 4 yrs ago but the hairs from the cocoon can last several years on the ground so mowing stirs them up and gets them airborne, I'm sure there in my red oaks but they're in the 60'+ class where i couldn't address them, When their dormant in winter or early spring, You can cut the branch with the nest, Place in a bucket of soapy water or burn them to get rid of them but you would need to involve a neighborhood to do it to try to eradicate them and most don't even know what they are or even look like.