Beginning to fear for my maple
The picture is part of an autumn blaze maple that we planted in 2009. The trunk caliper at the time was probably 3 inches. The trunk has not gained much since then. It has not developed the taper at the soil level.
Over the last 4-5 growing seasons, this tree has not done much in the way of growing--branches have extended no more than 5 inches over the last 5 years. We do have other maples in the nearby area that are thriving. I realize when you buy a container tree that it takes a few seasons, but we're on season 5 now. Growth so far this year has been about 1 inch, whereas our autumn flame maple and crimson king have much, much more than that already.
What has me worried is the branch in the picture. This is one of the branches that was 'pruned' before the nursery shipped it--so it has always had a snaggly tip at the end. However, this branch leafed out in early spring...and last week the leaves wilted and shriveled.
I am beginning to fear verticillium wilt. Could I be on the right track?
The symptoms I see on my tree:
-very slow growth
-Blackish spots on leaves (small, and sparse)
Is there anything else to look for?
If it is this, can we treat it, or will this tree just languish in the backyard until we cut it down? (by the way, I'd really love to avoid that)