Hello. Thanks in advance for helping with this. This is about an infestation of a Royal Purple Smoke Tree, with possibly two types of insects. I was gone 1 week and returned home a week ago to find that insects had suddenly and significantly damaged the tree, which had been healthy. The leaves have the stained-glass effect as they're eaten. (Photos are attached -- zoom in.) The insects look similar to a striped black slug, but I don't think it's a sawfly -- It's been two weeks and no winged insects have appeared. And it's been dry. Yesterday I also found tiny tiny black spiders and a symmetrical bundle of white eggs. Also, during these 2 weeks, many leaves have tiny pieces of black debris on them, as though someone sprinkled bits of charcoal embers. Those bits also fall to the ground and look like black dirt. I've heard that trees can recover from this type of damage, but I'm concerned this one won't. Can someone help me identify what the infestation is, and what to do? I hope to avoid pesticides if possible. Thanks again.