Question: Is leatherleaf mahonia invasive?
Yes! Because of its adaptability to many sites this evergreen shrub, also known as Beale’s Barberry, can easily take over large areas. Invasive plant species are non-native species whose introduction is likely to cause economic or environmental harm. They often crowd out native plant species. Leatherleaf mahonia is a Chinese import, has naturalized throughout the southeastern U.S., and is now considered invasive.
Leatherleaf mahonia (Mahonia bealei) spreads by seed from birds eating the berries. It can colonize by basal sprouts (sprouts from a plant’s root), forms dense thickets, and is distasteful to deer.
Two excellent native alternatives to consider: Wax Myrtle (Myrica cerifera) and American Beautyberry (Callicarpa americana). If you currently grow leatherleaf mahonia, you should periodically inspect other areas of your garden for seedlings and consider the negative impact they can have on native plants on your property and in the community.
You may want to check out the Piedmont Native Plants Guide for Landscapes and Gardens and look at NC State University’s site for Urban Landscaping for Wildlife with Native Plants for more ideas on identification, control, and alternative native species.
References
Blue Ridge Prism, Partnership for Regional Invasive Species Management
“Invasive, Exotic Plants of the Southeast: Oregon Grape, Leatherleaf Mahonia”, NC State University
“Tried and True Native Plants To Replace Problem Plants, PROBLEM PLANT: Leatherleaf Mahonia (Mahonia bealei)”, Extension Master Gardeners of Northern Virginia, Virginia Cooperative Extension
I find it to be a polite invasive. It sporadically shows up here and there and Ive never seen it overwhelm an area like privet or bradford pear.
Do you know if Mahonia confusa is invasive in PIEDMONT NC?
I have not found any research that says it is invasive in our area. It is a non-native though.