Eradicating Sweet gum suckers - Ask Extension
A very large sweet gum was removed from my son's property this summer and now hundreds of suckers are coming up from the roots. I've cut some and use...
Knowledgebase
Eradicating Sweet gum suckers #814727
Asked October 20, 2022, 9:48 AM EDT
A very large sweet gum was removed from my son's property this summer and now hundreds of suckers are coming up from the roots. I've cut some and used Round Up concentrate on the cut ends. Do you think Brush Master would be a better solution or are they pretty much the same?
Charles County Maryland
Expert Response
The active ingredients in each are different, and if any desirable tree or shrub roots from live plants are still growing in the area to be treated, the dicamba component of the Brushmaster herbicide is not safe to use over top of them and may cause dieback. According to the label precautions, Brushmaster also might be more able to contaminate groundwater, especially in very permeable (sandy, in this case) soils. Glyphosate, the active ingredient in Round Up, binds more tightly to soil and is less likely to move into groundwater in the same way. The label for Brushmaster seems to state that one treatment per year is the application limit in this usage, whereas you might be able to re-apply glyphosate more than once a year if needed (check its label as there are many different formulations using glyphosate).
Both products will potentially kill any desirable plants (turfgrass, groundcovers, etc.) that the spray contacts during treatment, and it may take some time (days or weeks) for the treatment to move fully down into the roots to suppress future suckers, so you won't necessarily see sucker dieback right away. Given that sucker regrowth is very unlikely now (at the end of the growing season) even if the roots are still alive, you'll have to wait until spring to see how many suckers reappear, if any.
If you wish to avoid more chemical use, the simplest solution is to just keep cutting down all Sweetgum suckers that reappear. By depriving them of the chance to photosynthesize, they won't be able to replenish the root energy reserves (each resprouting uses-up some of that stored energy), and eventually the root system growing the suckers will starve and die out. Denying the suckers light by smothering them with a material like landscape fabric (which blocks light but allows moisture and oxygen to reach the soil, which is important) can also work, but may be less practical if there are desirable plants growing between them since you can't deny them light for that long. After suckers stop returning, you can remove the fabric cover and mulch or replant the area.
Miri
Both products will potentially kill any desirable plants (turfgrass, groundcovers, etc.) that the spray contacts during treatment, and it may take some time (days or weeks) for the treatment to move fully down into the roots to suppress future suckers, so you won't necessarily see sucker dieback right away. Given that sucker regrowth is very unlikely now (at the end of the growing season) even if the roots are still alive, you'll have to wait until spring to see how many suckers reappear, if any.
If you wish to avoid more chemical use, the simplest solution is to just keep cutting down all Sweetgum suckers that reappear. By depriving them of the chance to photosynthesize, they won't be able to replenish the root energy reserves (each resprouting uses-up some of that stored energy), and eventually the root system growing the suckers will starve and die out. Denying the suckers light by smothering them with a material like landscape fabric (which blocks light but allows moisture and oxygen to reach the soil, which is important) can also work, but may be less practical if there are desirable plants growing between them since you can't deny them light for that long. After suckers stop returning, you can remove the fabric cover and mulch or replant the area.
Miri
