Infos about butterfly-trees
a couple of trees near where i live (Stockholm, Sweden) have been
invaded by what i assume to be butterfly larvas. I would like to get
some infos about that. What kind of butterfly will it be? Is this
common? Is this repeating itself each year?... Do they all "mutate"
around the same time? Is it bad for the tree? ....
Any info would be much appreciated :)
ps: I posted some photos of the trees here: