Dogbane: A Toxic Lookalike of Edible Milkweed

The dogbane genus is known as ‘Apocynum’, and it contains three notable species, as well as a few hybrid species too. The species include hemp dogbane (Apocynum cannabinum), spreading dogbane (Apocynum androsaemifolium), and sword-lead dogbane (Apocynum venetum). All dogbane species have striking similarities to the edible milkweed plant, however, dogbane is not edible…

The common name ‘dogbane’ has been given to a number of plant species across history. As the name hints, it’s a plant that was initially considered toxic to dogs. However, dogbane is toxic to all mammals, including humans.

What Are The Active Compounds in Dogbane?

The milky sap within dogbane contains cardiac glycosides. These active compounds can also be found within foxglove which is another very deadly plant. The cardiac glycosides are toxic to all mammals, as they can have a detrimental effect on heart rate by slowing or increasing heartbeats. Dogbane roots contain the cardiac glycoside, cymarin, which has been identified as a cardiac stimulant.

These toxins remain even when the plant is dried. This means livestock could still be poisoned if plants are accidentally collected and distributed within hay.

Dogbane Poisoning Symptoms

While dogbane doesn’t have the extreme toxicity of manchineel or hallucinogenic datura, it can still cause a series of potentially deadly symptoms. Initial symptoms usually involve nausea, vomiting, diarrhea, increased urination, and convulsions. In serious poisoning cases, severe weakness, coma, and death can occur. Treatment is possible in mild cases, and it usually follows the same route of care involved in foxglove poisoning.

What is the Medicinal Potential of Dogbane?

Despite its toxic compounds, dogbane has been used in some American and European remedies. Native Americans created treatments for various respiratory illnesses, heart palpitations and even increasing milk flow in lactating mothers.

In Europe, it was often used as a substitute for foxglove (digitalis) and would be used in treatments for edema and specific heart conditions. The leaves of sword-leaf dogbane (Apocynum venetum) have a history of use in China as a medicine for hypertension, edema, and palpitations.

Cultural Symbolism of Dogbane

Because of its varied uses, dogbane (Apocynum cannabinum) has received a number of colloquial names throughout history. Hemp dogbane, Indian hemp, and wild cotton, all refer to the usefulness of its fibers in daily life. When dried, dogbane stems become very woody, fibrous, and tough. Native Americans used them to make nets, straps, bowstrings, and also simple twine, which had endless usage in daily life, including sewing clothes and equipment. It has also been known as rheumatism root, because of its use in treating inflammations and arthritis.

What Does Dogbane Look Like?

Plants can become quite tall and slender, usually reaching about 2ft. The leaves are opposite and pointed (lanceolate). The stems have prominent red coloring and are hairless, whereas the leaves have white hairs underneath. Dogbane flowers are quite delicate and showy, they’re bell-shaped and have a white to pink hue.

In Spring, dogbane and milkweed shoots can look very similar, and even grow in similar habitats, so foragers must take care. The flowers of dogbane eventually develop into long seed pods, full of fluffy seed heads.

Where Does Dogbane Grow?

Dogbane can be found growing in a variety of habitats, from urban areas of disturbed soil to woodland edges and sandy fields. The Apocynum cannabinum and Apocynum androsaemifolium species are native to North America, Canada, and parts of Mexico. 

The sword-leaf dogbane (Apocynum venetum) however is native to southeast Europe and many countries within Asia. It favors more waterlogged soil and can be found in coastal marshes and inland swamps.

Conclusion

Definitely a plant to be aware of if you plan on foraging milkweed. Although toxic, dogbane can still be enjoyed for its showy flowers and its vital place within ecosystems. The delicate pink flowers also provide a food source for plenty of insects too.

Featured Image: Spreading Dogbane Photo by Jacob W. Frank on Wikimedia Commons