Please don't kill insects unless you really need to, I've seen people on Facebook talking about destroying caterpillar nests because they kill trees and it's not even true they might eat some leaves but it's natural and doesn't usually kill the tree. Now I hardly see the nests anywhere anymore and the butterflies either.
We had a massive gypsy moth outbreak this year. They destroy oak trees and no birds will eat them. It's absolutely a good idea to destroy their nests. Obviously this entails knowing what they look like...
