Scientific name: Rhamnus cathartica L.
Common name: European buckthorn
Description: This shrub or small tree may reach a height of 26 feet. The simple opposite leaves are broadest at or above the middle and have a sharp point at the tip. Bisexual and sometimes unisexual flowers occur in few-flowered clusters in the junction of the leaves. Individual flowers lack petals, but have a four- to five-lobed calyx. The black berry-like fruits (drupes) are solitary or are grouped in two to five berries per cluster. Each fruit is juicy and contains three or four seeds. This species is very hardy and resistant to insect attack.
Occurrence: This European native has escaped cultivation and has become naturalized throughout Eastern North America along fence rows and in vacant lots and open woods.
Toxicity: Buckthorn contains a glycoside from which a strong laxative, anthraquinone, is derived by hydrolysis. Poisoning from eating the leaves and black juicy fruits has been reported from Europe. Cascara buckthorn (“Rhamnus purshiana” DC.), a native of the Pacific Northwest, also is poisonous.
Symptoms: Poisoning is characterized by moderate to severe stomach cramps and diarrhea.