Tree of hEAVEN - Ask Extension
I had a tree that phone identification apps told me was a Black walnut tree, growing next to my air conditioning unit at a rapid rate. Late last year ...
Knowledgebase
Tree of hEAVEN #874639
Asked June 25, 2024, 1:13 PM EDT
I had a tree that phone identification apps told me was a Black walnut tree, growing next to my air conditioning unit at a rapid rate. Late last year I cut it down to the stump, and this year it began sending off many small shoots nearby, which i have cut back numerous times, only to see them back twice as tall a few weeks later. I looked a bit more into the leaf shape and now I think this may be an invasive tree of heaven. I tried searching forums to find a relatively safe way of killing it, and the consensus seems to be to combine "Stump Stop" with "Adios" surfactant mixed in. I have never done anything like this and was hoping to avoid killing all the native aster and black eyed susan's growing nearby. Is this the right way to go about killing this tree?
Baltimore City County Maryland
Expert Response
Can you share a photo of the foliage? Black Walnut, Sumac, and Tree of Heaven can look very similar to each other, and ID apps aren't always accurate. Any of those three species could sucker (regrow new stems/trunks from the root system or trunk stump) after being cut.
If the plant is Tree of Heaven, the most effective and efficient way to kill them permanently is to treat the lower trunk with systemic herbicide (while it is still alive, not after it's cut), then wait about a month for it to fully kill the roots, then cut it down. Herbicide applied in this way should not affect nearby plants, since it remains in the tree's tissues. Commonly-used systemic herbicide ingredients include either glyphosate or triclopyr, but as with any non-selective chemical, they have the potential to harm other plants if drips from a spray land on desirable plants, so use them carefully. The page linked above has more information.
The herbicide brand you mention looks like it uses triclopyr as the active ingredient. We don't test or recommend specific brands or products of herbicides, but the active ingredient, plus the directions for use on product label itself, are the important features. A surfactant can be useful to add to herbicides in certain situations, but it might not be needed in this case...check with the recommendations on the herbicide label (some may say to use one, some may already contain one or be incompatible with one) and the label of the surfactant itself.
If you prefer to avoid any herbicide, the recourse will be a continued cutting-down of all sucker growth, as often as it appears, and as promptly as possible. This is done to starve the roots, because each resprouting uses-up root energy reserves, so eventually the plant will exhaust itself and die. With mature or well-established Tree of Heaven, though, this process might take well over a year to achieve success.
Miri
If the plant is Tree of Heaven, the most effective and efficient way to kill them permanently is to treat the lower trunk with systemic herbicide (while it is still alive, not after it's cut), then wait about a month for it to fully kill the roots, then cut it down. Herbicide applied in this way should not affect nearby plants, since it remains in the tree's tissues. Commonly-used systemic herbicide ingredients include either glyphosate or triclopyr, but as with any non-selective chemical, they have the potential to harm other plants if drips from a spray land on desirable plants, so use them carefully. The page linked above has more information.
The herbicide brand you mention looks like it uses triclopyr as the active ingredient. We don't test or recommend specific brands or products of herbicides, but the active ingredient, plus the directions for use on product label itself, are the important features. A surfactant can be useful to add to herbicides in certain situations, but it might not be needed in this case...check with the recommendations on the herbicide label (some may say to use one, some may already contain one or be incompatible with one) and the label of the surfactant itself.
If you prefer to avoid any herbicide, the recourse will be a continued cutting-down of all sucker growth, as often as it appears, and as promptly as possible. This is done to starve the roots, because each resprouting uses-up root energy reserves, so eventually the plant will exhaust itself and die. With mature or well-established Tree of Heaven, though, this process might take well over a year to achieve success.
Miri
Thanks for your detailed response. Here is a photo of the tree if you can help verify.
Thank you for the photo. The good news is that this is definitely not Tree of Heaven, though it's also not Black Walnut or Sumac because the leaf shape is not right for those either. Instead, it looks like an Aesculus (the genus to which Buckeye and Horsechestnut belong). Several species of Aesculus grow sporadically in Maryland natural areas (and they are also grown in gardens), though none are locally native.
The approach to removal doesn't change, and remains either repeated cutting-down or digging up, or treatment with a systemic herbicide.
Miri
The approach to removal doesn't change, and remains either repeated cutting-down or digging up, or treatment with a systemic herbicide.
Miri
