TreeRM

Common buckthorn

Rhamnus cathartica · Rhamnaceae · also European buckthorn, Purging buckthorn

A thorny, multi-stemmed shrub or small tree with glossy oval leaves that stay green late into fall, dark peeling bark with orange inner wood, thorn-tipped twigs and clusters of black berries on female plants that birds eat and scatter (the fruit is a purgative, hence the name). Planted as hedging in the 1800s, it now forms impenetrable thickets in woods and fencerows from Saskatchewan to Nova Scotia and across the Upper Midwest and Northeast, shading out everything beneath and hosting soybean aphid and oat crown rust. It is banned or restricted in most states where it grows.

Broadleaf, loses its leaves in winterFast growingSun or part shadeModerate water
Common buckthorn
Köhler, F. E. (Franz Eugen), Public domain, via Wikimedia Commons

Where it stands

Native

This tree evolved here, and local wildlife depends on it.

  • 🇩🇪 Germany · Native to Europe, northwest Africa and western Asia.source

Invasive

It escapes into natural areas and displaces native plants. Check your state's list before buying one.

  • 🇺🇸 MA, United States · Rated Invasive by the Massachusetts Invasive Plant Advisory Group and banned from sale under the state Prohibited Plant List.source
  • 🇺🇸 PA, United States · On Pennsylvania DCNR's invasive plant fact sheet list.source

Prohibited

Selling or planting it is banned here.

  • 🇨🇦 ON, Canada · Listed as a Noxious Weed under Ontario's Weed Control Act and as invasive by the Ontario Invasive Plant Council.source
  • 🇺🇸 CT, United States · Invasive on the Connecticut Invasive Plant List; sale and movement prohibited by statute.source
  • 🇺🇸 IN, United States · Regulated under Indiana's Terrestrial Plant Rule: illegal to sell, distribute or transport.source
  • 🇺🇸 MN, United States · Restricted Noxious Weed in Minnesota: cannot be imported, sold or transported.source
  • 🇺🇸 NH, United States · On New Hampshire's prohibited invasive species list (Agr 3800).source
  • 🇺🇸 NY, United States · Prohibited invasive species under 6 NYCRR Part 575.source
  • 🇺🇸 WI, United States · Restricted under Wisconsin NR 40.source

Care

Not for planting. Removal: pull seedlings when the soil is moist; cut larger stems and treat stumps immediately with triclopyr or glyphosate, ideally in fall or early winter when natives are dormant. Expect to return for several years because seeds stay viable in the soil.

Benefits

Birds

Good for

Hedgerow

Watch out for

Invasive elsewhereThornsToxic partsMessy fruit