These pesky alien-like creatures protected in their camoflaged cocoon emerge in the evening to feast on my arborvitae trees. They are bagworm caterpillars and they are killing my trees. We have a row of arborvitae trees that line our driveway and so far, we have had to replace two of them which were devoured by bagworms and by the looks of it, one more will have to be replaced. If we are lucky, we will be able to control the infestation by spraying insecticide or simply plucking them off the trees. The cocoons that the bagworms have formed look like pine cones, so they easily blend in looking like part of the tree.
The bagworms will continue to grow and feast and molt until August, so we have to inspect the trees daily for new cocoons. Unfortunately, the presence of bagworms often goes unoticed until they are mature and the damage is extensive! Wish me luck in my extermination efforts!