c1nicolei, they have never killed my trees.

I worked with a guy that got the idea of freezing them so he could keep them for fish bait. He put them in the freezer and his container turned over and they crawled all over the freezer before they froze. He was not happy when his wife made him clean out the freezer to get rid of them.

They will not kill the catalpa trees. I know this as fact because I have grown up with catalpa trees and watching the worms eat their leaves every year, my next birthday I will be 65 yrs. old and have never saw a catalpa tree die from the worms eating the leaves off of them. The tree may die from disease. The worms are good fish bait, I know this for a fact also. The naked trees will look terrible but will come back I know of some catalpa trees that are over 100 yrs. old and get eaten every year. The worms are nasty with their droppings.

Think of it this way...the tree and the caterplillar evolved to depend on each other (I'm making an assumption that the adult moth probably pollinates the flowers..that's the way thing usually work out). Neither wants the other to die (evolutionarily speaking)...and the tree has produced an annual crop of leaves, which would be slated to begin falling in about a month anyway...the caterpillars simply hurry it along a little bit, the tree takes no real harm, just a slight loss of possible photosynthetic time.

Good to know, it is astounding all the pop on the ground from all their munching. Thrilled to hear my beautiful tree will survive!

If it is a dry there as it is here the loss of leaves may be a good thing - less water loss through the leaves. I had my big walnut tree removed after the Joplin tornado scared me about a huge tree over the house. I do not miss the raining poo at all.