Glossy Buckthorn

Frangula alnus

Glossy buckthorn berries
 Image credit: Sigrid Resh

Characteristics

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

  • dark green, oblong leaves with a smooth margin, a shiny underside, and 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
  • small, green-yellow flowers, clustered, with four petals

Note: Commonly mistaken with dogwood, to tell the difference between them look for the shiny underside of the glossy buckthorn’s leaf and dogwood leaves have white strings that are visible when leaves are torn apart carefully.

For more information visit WiGl and 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 fast. It is very important to start removal of Buckthorn before seed production and to remove fruit bearing trees when found for best results. Here at KISMA, buckthorn is another major invasive species that we have at multiple sites. It’s important to revisit sites 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 to 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 still cannot be removed with the weed wrench, cut the tree a few inches above the ground and securely cover with a thick trash bag, using zip-ties, to help 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.

 

Glossy buckthorn infestation
(image credit: Sigrid Resh) glossy buckthorn overcrowding the understory
Glossy buckthorn roots
(image credit: Sigrid Resh) glossy buckthorn stem and root system
glossy buckthorn sapling

(image credit: Sigrid Resh) new leaves on sapling

bagging buckthorn stump to smother stump sprouts

(image credit: Sigrid Resh) securely fastened plastic bag used to smother buckthorn stump sprouts after cutting

Sources

“Glossy Buckthorn (Rhamnus frangula).” MISIN, 2020. 

“Recommended Plant List.” NMISN, 2017.