Glossy Buckthorn

Frangula alnus

Characteristics

Glossy buckthorn, a small, woody tree from the Rhamnaceae family, is an understory invasive that produces large amounts of seeds and outcompetes many native species. It’s also both sun and shade tolerant and can live in many different soil, moisture, and habitat conditions. Identifying characteristics of glossy buckthorn include:

• dark green, oblong leaves with a smooth margin, a shiny underside, and a glossy surface. Veins also bend towards the tip
• stems are brown, turning gray with age, and covered in very prominent white lenticels
• produce numerous black, round drupes from July-September
• flowers are small, clustered, green-yellow, and have five petals

Note: Glossy buckthorn is commonly mistaken with dogwood. A key difference between these two species is that the underside of glossy buckthorn leaves are shiny, whereas the underside of dogwood's leaves are not. Additionally, when torn apart carefully, dogwood leaves will have white strings.

For more information visit Woody Invasives of the Great Lakes (WIGL) Collaborative and Midwest Invasive Species Information Network (MISIN).

KISMA Management Practices

Buckthorn is a highly aggressive species that produces copious amounts of seeds and saplings and is able to take over an understory relatively quickly. It is crucial to start removing buckthorn before seed production and to remove fruit bearing trees when found for the best results. Here at KISMA, buckthorn is another major invasive species that we have at multiple sites. It’s critical to revisit sites after management as buckthorn seeds are viable in the ground for multiple years and it’s important to remove all seedlings. KISMA prioritizes removal of seed trees and satellite populations first, to prevent further spread of buckthorn. 

1. hand-pull small seedlings and saplings
2. for stems too large to hand-pull, use a weed wrench to loosen the roots. After roots are loosened the tree should be easy to remove with hand pulling
3. if the tree is too large for the weed wrench, cut the tree a few inches above the ground and cover with thick trash bag, secure bag to stump with zip tie, spread bag over soil around stump, and weigh bag down with rocks or wood. Leave bag in place for two growing seasons. This smothering technique will prevent stump sprout regeneration and kill the root mass.

Note: It's very important to remove seeds and seed-bearing trees first, as this is the main reproduction strategy of buckthorn.

Native Alternatives

Species that are excellent native alternatives to glossy buckthorn are native dogwoods like red-osier dogwood (Cornus sericea) and flowering dogwood (Cornus florida). Serviceberry (Amelanchier sp.) is also a great alternative providing a well needed food source for native wildlife. Other species such as highbush cranberry (Viburnum trilobum) and other native shrubs are great as well.