Identification
Alder Buckthorn (Frangula alnus) is a multi-stemmed shrub or small tree reaching 10-23 ft. It features glossy green, oval leaves with smooth (entire) margins and 6-9 pairs of prominent parallel veins. Bark is gray-brown with white horizontal lenticels; inner bark is lemon-yellow.
Habitat
Native to Eurasia but invasive in TN/KY, it thrives in wet, acidic soils, wetlands, riverbanks, and damp woodlots.
Ecological Role
Invasive species that shades out native flora. While birds eat the berries, the purgative anthraquinones cause seeds to pass quickly, aiding spread but providing poor nutrition.
Agricultural Value
No positive value; it is an aggressive pasture weed that displaces useful forage.
Toxicity
High toxicity due to anthraquinone glycosides (emodin). It acts as a severe irritant laxative.
Vet Response
Remove from source immediately. Triage involves hydration support and toxin removal. Monitor for bloating and diarrhea.
History
Historically used in Europe as a laxative and for yellow/brown dyes.
Foraging/Cultivation
Do not cultivate; removal is a priority. Berries are purgative and dangerous if consumed.
Chemistry
Contains anthraquinones like emodin.
Navigation
Presence indicates moist to wet soils; in native ranges, used as a landmark in wetland margins.