Apocynum cannabinum


Apocynum cannabinum is a perennial herbaceous plant that grows throughout much of North America - in the southern half of Canada and throughout the United States. It is a poisonous plant: Apocynum means "poisonous to dogs". All parts of the plant are poisonous and can cause cardiac arrest if ingested. However, some Lepidoptera feed on this plant, such as two hummingbird moths. The specific epithet cannabinum and the common names hemp dogbane and Indian hemp refer to its similarity to Cannabis as a fiber plant, rather than as a source of a psychoactive drug.
Although dogbane is poisonous to livestock, it likely got its name from its resemblance to a European species of the same name.

Description

Apocynum cannabinum grows up to tall. The stems are reddish and contain a milky latex capable of causing skin blisters. The leaves are opposite, simple broad lanceolate, long and broad, entire, and smooth on top with white hairs on the underside. It flowers from July to August, has large sepals, and a five-lobed white corolla. The flowers are hermaphrodite and are pollinated by moths and butterflies.

Distribution and habitat

Apocynum cannabinum grows in open wooded areas, ditches, and hillsides. It is found in gravelly or sandy soil, mainly near streams in shady or moist places.
This species is native to North America. However, in gardens it can be unwanted, growing from spreading roots. When growing among corn, Apocynum cannabinum can reduce yields by up to 10% and when growing among soybeans, by up to 40%. It can be controlled through mechanical means, although it is difficult to control with herbicides.

Ecology

The plant serves as a larval host for the snowberry clearwing and hummingbird clearwing moths. These moths are pollinators that resemble small hummingbirds.

Uses

The plant can be used for various purposes. The most used parts are the seeds, the root, and the bark.

Fiber

Apocynum cannabinum was used as a source of fiber by Native Americans to make bows, fire-bows, nets, tie down straps, hunting nets, fishing lines, and clothing. It is called qéemu in Nez Perce and in Sahaptin. The Concow tribe call the plant pö.

Food

The seeds have an edible use as a meal when ground into a powder.

Chewing gum

After the latex has been squeezed from the plant, it is allowed to stand overnight to harden into a white gum which can be used as chewing gum.

Phytoremediation

Apocynum cannabinum is a phytoremediation plant, a hyperaccumulator used to sequester lead in its biomass.

Medicinal

It is also used in herbal medicine to treat fever, and dysentery. Although the toxins from the plant can cause nausea and catharsis, it has also been used for slowing the pulse, and it is also a sedative and mild hypnotic. It is an unpleasantly bitter stimulant irritant herb that acts on the heart, respiratory and urinary systems, and also on the uterus. Apocynum cannabinum was much employed by various Native American tribes who used it to treat a wide variety of complaints including rheumatism, coughs, pox, whooping cough, asthma, internal parasites, diarrhoea and also to increase milk flow in lactating mothers. The root has been used as a tonic, cardiotonic, diaphoretic, diuretic, emetic and expectorant. It is harvested in the autumn and dried for later use. The fresh root is the most active part medicinally. A weak tea made from the dried root has been used for cardiac diseases and also as a vermifuge. The milky sap is a folk remedy for venereal warts. The plant is still used in modern herbalism, though it should be used with great caution and only under the supervision of a qualified practitioner if taken internally.