Read the info you provided about the insect. I am a little confused when you say they are basically harmless. Back east where I come from, they defoliated huge areas. Now I am living in Az. in an area where we have never seen them before, but I am suddenly inundated with them. They seem to be everywhere in mass quantities. They are climbing the Hackberry trees, our primary source of shade. Is it likely they will defoliate them? If so, what can be done? Thanks in advance for any info.