An invasive shrub with big plans for domination.
Species Name: Common Buckthorn, European Buckthorn (Rhamnus cathartica)
Description: A deciduous shrub or tree (up to 25 ft) with dark green, oval-shaped leaves that produces clusters of green-yellow four-petaled flowers in Spring followed by small round fruits, ranging from green to red to black. Twigs often bear a single thorn at the tip. The inner bark is distinctively orange when exposed by scraping the stem. Common Buckthorn can be found in abandoned fields, along roadsides, and at the edge of woodlands.
Similar species: Glossy Buckthorn (Frangula alnus), also an invasive shrub, has five-petaled flowers and more leaf veins than Common Buckthorn. Alder-leaved Buckthorn (Rhamnus alnifolia), a native buckthorn, remains under three-feet tall, grows primarily in wetlands, and has petal-less flowers.
Origin: Eurasia. It was planted in the United States as an ornamental shrub and was popular in conservation plantings.
How it spreads: The many fruits produced by Common Buckthorn are well-dispersed by birds and mammals; the plant will resprout when cut.
Extent in Michigan: Throughout Michigan, especially in areas of past disturbance.
Why is Common Buckthorn a problem: Common Buckthorn can quickly establish and outcompete native plants, decreasing diversity and limiting food sources for native wildlife. Common Buckthorn can also alter the nitrogen cycling of soils. This buckthorn can also be an alternate host for several agricultural pests. Common Buckthorn is difficult to control as it can resprout from the stumps and roots of cut plants.
Management actions/options: Common Buckthorn can be treated with hand cutting or pulling but the most effective method of removal is through the cut-stump application of herbicides. Several resources are available for planning a control treatment, please refer to the links at the bottom of this post.
REPORT IT: Use the Midwest Invasive Species Information Network Reporting tool online
or download their reporting app
Links and References:
Michigan DNR: http://www.michigan.gov/documents/dnr/Common_Buckthorn_389115_7.pdf
Minnesota DNR: http://www.dnr.state.mn.us/invasives/terrestrialplants/woody/buckthorn/control.html