European and Glossy Buckthorn - Rhamnus cathartica and R. frangula
General Description
Buckthorns are tall, deciduous shrubs that can reach heights of 25 feet. They form dense thickets that crowd out most other plants. These species tolerate many different conditions, allowing them to inhabit various communities including open woodlands, riparian woodlands, forest edges, old fields, and fens.
Identification
Both buckthorns have dull green, ovate, glabrous leaves that are slightly serrated. European buckthorn has alternately arranged leaves, while those of glossy buckthorn are opposite. Bark is gray-black and twigs have prominent lenticels. Berries are black when ripe. Twigs are smooth and may be tipped with sharp stout thorns. Greenish-yellow flowers are fragrant, may number from 2 to 6, and have four petals.
Origin
Buckthorn is native to most of Europe, as well as north and west Asia. It was introduced into North America prior to 1800 as an ornamental hedgerow.
How It Spreads
Birds feed on the fruits, spreading the seeds to create new buckthorn colonies.
Control Methods
Buckthorn is controlled from April through September. Hand pull small seedlings. Cut larger plants at six inches and paint cut surfaces with a 10% glyphosate solution. Spray foliage on large populations of young shrubs when there are no other species nearby.
