Homegrown: Pagoda tree, grinding stumps
We have a large, 45-year old-Japanese pagoda tree in our front lawn. For several years, the tree has dripped sap from a location where a large branch was cut away. The sap has burned a 2-foot diameter hole in the grass.
There are a couple of other locations on the tree where sap drips from spots where larger branches were removed. Is there a way to seal the branch removal site?
It sounds like your tree has a bacterial disease called Wetwood. It’s actually a pretty common occurrence in the Grand Valley on cottonwoods and elms, but it also occurs in a wide variety of other trees.
What this disease does is ferment the wood of the tree; in essence, it’s making “pagoda tree wine.”
The disease is characterized by a wet patch of bark or sap bleeding down the trunk. The ooze can be bubbly sometimes, but not always.
The ooze will often smell sour or like stale beer. It often attracts insects, but they’re not hurting the tree, they’re feeding on the goo that’s leaking from the tree.
It’s also pretty common for the ooze that runs to the ground to kill the lawn, as it seems to have done in your case.
The disease needs a wound to enter the plant. Most often (as with your tree), the infection starts in a pruning wound, but it also can occur at a branch junction since there are often miniscule cracks that occur as the branch moves in a strong wind.
Wetwood is common. I’d guess that most, if not all of the older cottonwoods and elms in the valley have it.
It also is a funny kind of disease in that a healthy and strong tree can coexist with the disease for years if not decades. The disease sometimes can fade in and out — it’s bleeding this year, but not next, then it bleeds for a couple of years, then doesn’t for some more.
The disease is never really gone. It’s just sort of goes into hiding.
There really isn’t anything to do directly for the disease. The bacteria extend into the heart of the tree and we can’t get chemicals in to kill it there.
About the only thing you can do is to take as good of care of the tree as possible. Make sure that it is watered deeply, but infrequently. Control any insect problems that may crop up. Avoid preventable stresses such as physical damage to the roots or trunk. Just common sense stuff.
As long as the tree is healthy and happy, it will usually live with the disease for years to come.
We need to grind several stumps. I assume I need to put the Fertilome Brush & Stump killer on to completely kill them. Do I put it on after the trees are removed and before the stumps are ground? Or can I put it on after the stumps are ground?
I suppose the best way would be to treat the stump with the Brush & Stump Killer first, wait several weeks to allow it to completely kill the stump and then have it ground down.
Treating the stump after it’s ground down is difficult.
At that point, probably the best thing for you to do is to treat the suckers (at the diluted rate on the label) with the Brush Killer as they appear. You’ll have to do it several times, but you should be able to get them all killed off.