White fluffy balls on maple trees

Q. We have three younger maple trees and they all have these white web/sac like things on the branches. Do I need to worry about them or treat them somehow??

A. From your photo, it looks like you have Cottony Maple Scale. Trees are very tolerant to this scale and it does not usually harm them. It is generally managed by its natural enemies, which are certain beetles, wasps, and flies. Insecticides are rarely needed. Here’s a link to an article from Michigan State University to explain further.