Buckthorn: A Tale of Two Trees
For anyone interested in foraging or wild edibles, understanding the nuances of plant identification is not just a hobby, but a matter of safety. The name 'buckthorn' is particularly tricky, as it refers to a group of plants with vastly different edible properties. The two most prominent species are the edible sea buckthorn (Hippophae rhamnoides) and the poisonous common or purging buckthorn (Rhamnus cathartica). It is critical to know how to tell them apart, as their appearances can sometimes be confused by the inexperienced eye.
The Poisonous Common Buckthorn
Common buckthorn, an invasive species in many parts of North America, is highly toxic to humans. All parts of the plant, including its black berries, contain toxic compounds known as anthraquinones and emodin. Ingestion causes a severe laxative effect, stomach cramps, and other gastrointestinal distress.
- Key features of common buckthorn:
- Thorns: Sharp thorns are often present at the tips of twigs.
- Berries: Small, pea-sized, dark purple to black berries appear in clusters in the fall.
- Inner Bark: A distinctive orange inner bark is revealed when a twig is cut.
- Leaves: Oval-shaped with fine teeth on the edges and prominent veins that curve towards the tip.
Beyond its immediate toxicity, common buckthorn is an ecological menace. It outcompetes native vegetation, alters soil nitrogen levels, and contributes to soil erosion. Foragers should learn to recognize this invasive plant not only for personal safety but to help prevent its spread.
The Edible Sea Buckthorn
In stark contrast, sea buckthorn is a nutritional powerhouse, often dubbed a 'superfruit'. Its bright orange berries are rich in vitamins, minerals, antioxidants, and fatty acids. Although they are extremely tart and not typically eaten raw, they are used to make juices, jellies, syrups, and other culinary products.
- Key features of sea buckthorn:
- Thorns: Branches are typically very thorny.
- Berries: Vibrant orange berries cling tightly to the branches and are harvested in the fall.
- Leaves: Narrow, elongated, and silvery-green in color, with a shimmery appearance.
- Habitat: Commonly found in coastal areas, sand dunes, and alongside rivers and lakes.
To harvest sea buckthorn safely, foragers should use thick gloves to protect themselves from the thorns. Many experienced foragers freeze the branches first to make removing the berries easier.
Comparison Table: Common Buckthorn vs. Sea Buckthorn
| Feature | Common Buckthorn (Rhamnus cathartica) | Sea Buckthorn (Hippophae rhamnoides) |
|---|---|---|
| Berry Color | Dark purple to black | Vibrant orange |
| Berry Toxicity | Toxic, causes laxative effects | Edible, highly nutritious (but tart) |
| Inner Bark | Distinctive orange | Not characteristically orange |
| Thorns | Usually present at twig tips | Dense, sharp thorns on branches |
| Leaves | Oval with finely toothed edges | Narrow, elongated, and silvery-green |
| Habitat | Woodlands, fields, disturbed areas | Coastal regions and sandy soils |
| Ecological Impact | Invasive, crowds out native species | Can be invasive in some areas, but often planted for soil stabilization |
The Case of Other Lookalikes
When foraging, it's not enough to know the difference between common and sea buckthorn. Several other plants produce black or orange berries, and some are toxic. These include black cherry (Prunus serotina) with edible fruit but toxic leaves and seeds, and certain ornamental species of Cotoneaster. The only way to be certain is through positive identification using multiple features, including leaves, bark, berries, and thorns. If there is any doubt, the plant should not be consumed.
Conclusion
Ultimately, whether it is safe to eat buckthorn is not a simple yes or no answer. The key lies in precise identification. The common buckthorn is dangerous and should be avoided, while the sea buckthorn is a valuable, edible fruit. Foragers must equip themselves with thorough botanical knowledge and should never rely on a single characteristic. By learning to distinguish between these species, you can forage safely and enjoy the benefits of edible wild plants while avoiding the risks posed by toxic ones.
For more information on invasive species and their identification, consult authoritative sources like the Ontario Invasive Plant Council.
