Family Rhamnaceae

Common Buckthorn came originally from Europe, northwest Africa and western Asia.  It was introduced to North America as an ornamental shrub, but has escaped into the wild and is one of our most problematic and aggressive invasives.

The plants are dioecious – male and female flowers growing on separate plants.  The seeds have toxins that cause a laxative effect – possibly helping with seed dispersal.  (Wikipedia)

Both Wikipedia and Minnesota Wildflowers have useful information about this species.

We have buckthorn sprinkled throughout our woods.  We try to cut and treat the stumps of larger shrubs as soon as we find them, especially if they’re females, but there are so many that we never get to all of them.  Some places have very dense patches, and we’ve targeted some of those in our fall projects.  I pull the smallest plants, and cut and treat larger stems – or trunks – with Garlon 4 mixed with bark oil.  It’s easiest to find buckthorn in the fall because its leaves stay bright green until well into November – after most other leaves have changed color or fallen.

This shows buckthorn with its bright green leaves in mid-October, along the edge of the woods.

 

Buckthorn berries – mid-October

 

Male buckthorn flowers – late May

 

Buckthorn seedling – mid-November.  These are the first leaves of a new buckthorn plant.  At this stage the plant has a root about an inch long which can easily be pulled.

 

A young buckthorn plant with just a few leaves.  Small plants like this can also be pulled – their root systems are still small.

 

Bare branches still with some berries left – mid-March

 

In the middle of a buckthorn clearing project