I am a part of a volunteer group in local ancient woodland and we have very many trees there which I completely covered in Ivy, we can also from time to time expect high winds of up to 40 Mph gusts. This is in England so we have a variety of different kinds of trees and a reasonably diverse natural habitat which is left to mostly grow wild apart from really the work that we do.
I am aware of the fact that other woodland nearby does have any Ivy on its trees because the park keepers are there and paid to remove it since if it grows on the tree too much it becomes quite heavy and if said gusts come the tree can be more likely to be knocked over by it.
Generally I understand that it doesn't damage the tree much more than that though because the branches just push further outwards to get to the sunlight and the Ivy is actually quite good nesting material for the birds. So it certainly does serve its purpose.
But as many of the trees are quite tall there and old, they may have the falling over problem. So I going to write a letter to the management of the group to suggest surveying the woodland and then removing any Ivy which is becoming a danger.
But I wanted to be well informed first about what actually constitutes as actually 'dangerous' before contacting them so we know what to actually survey.
I could find anything on government websites about this or woodland sites. So I was wondering if there are any guidelines and an established definition of how much Ivy is too much? What the specific dangers there are if there is just too much of it covering the entire tree? And judging by the size of the tree and maybe type, how much Ivy is too much?
I searched around a bit but I really couldn't find a comprehensive guide on this.