How to Remove Leatherleaf Mahonia
These recommendations are primarily for homeowners and communities that would like to start working in their neighborhood greenspace. For each species we recommend herbicide-free control methods, but have added an herbicide option for some species for those who are comfortable using them. These methods were selected while keeping in mind limiting soil disturbance, reducing herbicide use, and avoiding harm to other species that may be present whether they be other plants/animals. Manual removal is possible for all of them if you have the time. If the infestation is overwhelmingly severe or these tips aren’t proving effective, we suggest you consider qualified professional services.
Leatherleaf Mahonia
Mahonia bealei – Georgia EPPC Category 3 (moderate problem in Georgia)
This species is difficult to uproot, has spiky sharp leaves, and will require follow-up control to successfully kill the same individual plant if herbicide is not used.
Uproot
Mahonia has a deep tap root and a brittle stem, making it very hard to uproot. We recommend using the cut and treat or cut and leave method.
Cut and Leave & Cut and Treat
If the tree or shrub cannot be uprooted, the best removal method is cut-and-treat. We suggest using a high concentrate (between 20-50%), glyphosate-based solution and add in an indicator dye to keep track of what has been treated.
Use a hand saw to cut down the tree or shrub, but be sure to prune off any protruding thorny branches so you are able to get to the base of the tree. Get the stump as close to the ground as possible, ideally less than 1” off the ground. If the tree or shrub has a larger diameter, getting closer to the ground will be more difficult and not as necessary as for a smaller diameter tree.
If you prefer not to use an herbicide (cut-and-leave), know that the stump will regrow. When it does, take pruners or a hand saw and remove all new growth as soon as you see it. This will eventually starve the roots, killing the plant.
First prune back any branches that may be blocking you, then make a weight cut at waist height if necessary.
For the cut and leave method, leave some length on the stump.
The stump should be treated with the herbicide within 5 minutes after the cut. We use 1-liter hand sprayers to apply the herbicide, but it can also be “painted on” using a brush to apply the solution to the cut. Be sure not to get the herbicide anywhere but on the stump you are treating. If the stump is not treated, or is not cut low enough, it will regrow.
Apply herbicide directly to stem within 5-10 minutes of cutting.
The debris can be piled neatly on site to dry and break down naturally. Temporary habitat will be created and nutrients will be recycled. Of course, debris can be taken offsite, if preferred.
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“Category” refers to description of invasiveness based on information from the Georgia and North Carolina Exotic Pest Plant Council (EPPC) and do not necessarily reflect the severity of invasions in Atlanta specifically. View our Resource “Atlanta’s Top Invasive Plants (A to Z) Expanded List” for more information.
A great opportunity to learn is volunteering with us at a Forest Restoration project. Please view our Calendar of upcoming service projects or consider enrolling in our annual Forest Stewardship training program. For other species removal, also read: How to Remove Our Top 10 Invasive Plants.
If you have any questions about this guide please email restoration@treesatlanta.org.
