Buckthorn (Rhamnus cathartica and Frangula
Glenn Nice, Weed Diagnostician, Department
of Botany & Plant
Pathology, Purdue University
You have probably heard the name buckthorn
before, primarily because of its association with the Asian
soybean aphid. Both
these species, common buckthorn (R. cathartica) and
glossy buckthorn (F. alnus), have been reported to be
over-wintering hosts for the soybean aphid.
Both species are shrubs or small trees, growing
up to 19 feet tall (Figure 1). Both buckthorns produce several dark berry-like
fruit (Figure 2 and 3). Common buckthorns have spines at
the ends of the stem (Figure 4) and have entire ecliptic-ovate
to round leaves (Figure 5 and 6). Glossy buckthorn’s
leaves are more lanceolate being longer than wide.
Both of these species have been introduced
to the US. Common
buckthorn is native to Eurasia and glossy to Eurasia and Northern
Africa. These buckthorns were brought into the US for the
use as hedges or wildlife habitat. Common buckthorn is
considered a noxious weed in Iowa, Minnesota and Vermont, and
an invasive weed in New Hampshire (http://plants.usda.gov). In
Indiana, common buckthorn has been reported in 15 counties and
glossy has been reported in eight counties (Overlease, 2002). In
an assessment done by the Indiana
Invasive Plant Species Assessment Work Group (IPSAWG) both
common and glossy were rated high for their potential for expansion
and difficulty of management.
The Purdue University Weed Ecology lab, headed
by Dr. K. Gibson, is presently investigating the ecology of
buckthorn in Indiana. For
more information please see the Weed
Ecology Lab’s Researching Buckthorn web page.
Overlease, William and Edith Overlease. 2002. 100
Years of Change in the Distrabution of Common Indiana Weeds. Unpublished.
Pictures courtesy of Purdue
University Weed Ecology Lab