I was going to do another tree-related topic first, but in response to Greg’s (?) request for some of today’s photos, I’ll switch. Girdling is anything that cuts off the movement of water and nutrients up from the roots to the leaves, or sugars made by the leaves down to the roots, all of which occurs in the outer layers of the tree, just under the bark. So if it’s all the way around it will kill the tree. It it’s part way around it will inhibit the growth.
I saw a couple of trees on Comm Ave. near BC today with these plastic ties, probably something to do with the Marathon. Anyone attaching things to city trees is supposed to get a permit, and anything like this should be removed after the event, because as the tree grows it will basically choke itself. I cut off the ones I saw, but if anyone notices anything like this on a tree, please remove it.
Another thing to look out for and remove is nursery tags. I noticed this almost invisible wire on a tree on Central Ave. in Newtonville. When the tree was planted years ago it would have been loose, but now it’s starting to cut into this branch (which probably shouldn’t have been allowed to get this big, but that’s another story). It’s nice to leave a species label on when a tree is young so people can see what kind it is, but it’s best to have it on a low, non-permanent branch, and definitely not around the trunk.
Another form of girdling is string trimmer or lawnmower damage that cuts through the bark. This pair of photos are, I think, the same tree by the Richardson St. parking lot in Newton Corner. At left is from July 2008, when I watched the three trees there get sideswiped by a rider-mower, apparently not for the first time. It’s on my way to the Y so I started weeding and mulching them so a lawnmower would never have to get that close again. (The worst damaged tree toppled over a couple of winters ago; the third tree is really struggling.) The right photo is this morning, showing suckers at the base which are a typical tree response to stress or damage. They need to be cut off, over and over again. I hope this tree at least will survive.