Most healthy trees can withstand a couple years of leaf loss from caterpillar damage. Long-term damage depends on the type of tree as well as how much defoliation took place:
- Hardwoods – A healthy leaf-bearing tree should have grown new leaves by now, though leaves may be smaller than usual. If your tree lost all its leaves and does not grow any new ones by summer’s end, watch it in the spring. If it still does not leaf out next spring, it has died.
- Conifers – If your needle-bearing trees lost more than 50 percent of their needles, there’s a good chance they probably won’t recover. Keep an eye on them in the coming seasons, and if you have concerns or think the tree could endanger a house if it were to fall, contact an arborist.