Eupatorium: Bonesets, Thoroughworts, Snakeroots/ DK: Hjortetrøst

Eupatorium purpureum, Sletterhage/photo:gb

Eupatorium is a genus of flowering plants in the aster family Asteraceae. They have from 36-60 species depending on the classification system. Most are herbaceous perrennial plants. A few are shrubs.

Most Euparium are called bonesets, thoroughworts or snakeroots. The genus is named for Mithridates Eupator, king of Pontus.

The habitat for Eupatorium is Asia, North America and Europe.











In Denmark are four species of  Eupatorium: (growing wild or cultivated:

Eupatorium purpureum, Red Hjortetrøst (introduced in DK in Middle Ages by monks)
Eupatorium cannabinum, Hamp- Hjortetrøst
Eupatorium rugosum,White Hjortetrøst (Ageratina altissima)
Eupatorium japonicum, Japansk Hjortetrøst
 
The Danish name Hjortetrøst ( meaning "consolation of the deer") refers to that people and hunters in the old days believed that a deer hit by an arrow was healed by eating the plant.

Eupatorium purpureum, wikipedia

Eupatorium purpureum, Red Hjortetrøst  is a vigourously growing  perennial with a stiff,upright growth. It is a fine garden plant. The pink flowers are gathered in small baskets, they are seen from July. The seeds sprout willingly.  It grows in the river valleys in the eastern and central USA and Canada. It  was introduced in Denmark in the Middle Ages by the monks in their kloster gardens. 

Eupatorium cannabinum, Hamp-Hjortetrøst , a perennial herb that grows on moist ground. It is wild-growing in Denmark but is also used as a garden plant. The pale red or pink flowers are seen in  July-September. The fruit is a nut. It is spread in North Africa, the Middle East, Asia Minor, Caucasia, Central Asia., Himalaya and China and in most of Europe. In Denmark it is common in the Isles and in East Jutland - or else very rare. It is overall connected to light-open and moist or wet ground with nutrient soil. It is among other places found at the banks of Gudenaa river. It is used as a garden perennial at garden ponds or along water streams and is much used in swampy areas in natural gardens.

Eupatorium cannabinum in old Danish folk medicine: It is said to contain similar healing properties as Agrimony. A decoct was recommended for liver and spleen. The plant was useful against malaria, jaundice, mange and itching. The juice was given for children's intestinal worms.Some meant it healed wounds. If a deer was hit by an arrow it was cured if it eat the plant. Hunters claimed that wounded deer eat the plant.  The flowerstalk was written in the pharmacopoeia in 1772. The plant was also mentioned as a means for horses with liver and lung disease.

Eupatorium rugosum/ Ageratina altissima, White Hjortetrøst or White Ageratina is an upright growing perennial with one or few hairy or smooth stems. The snowwhite flowers are seen in July- October . The fruits are dry nuts. It has its habitat in the northeastern USA and Canada where the plant is a part of the vegetations along forest glades and in the zone between forest and prairie . Grows wild in Denmark.

Eupatorium japonicum, is native to China, Japan and Korea. It grows wild in a few places in Denmark

Medicine

Medieval garden, wikipedia

The common names for the plants are all based on the previous usage of one species, Eupatorium perfoliatum, as an herbal medicine. The common name apparently derives from the herb's use to treat dengue fever, which was also called breakbone fever because of the pain that it caused. The name thoroughwort also comes from Eupatorium perfoliatum, and refers to the perfoliate leaves, in which the stem appears to pierce the leaf (i.e. go through, note that in older usage "thorough" was not distinguished from "through", compare for example the word thoroughfare).

Eupatorium rugosum contains some chemical connections, which are not poisonous in themselves but they change in the liver into very poisonous connections. Cows eating the plant excrete these poisonous conections in the milch, which then is deadly poisonous to humans (and the calves). The poisoning was called the milch-disease.Boneset, although poisonous to humans and grazing livestock, has been used in folk medicine for instance to excrete excess urid acid which causes gout. Caution is advised when using boneset, since it contains toxic compounds that can cause liver damage. Side effects include muscular tremors, weakness, and constipation; overdoses may be deadly.

Bjerreskov/photo GB

Eupatorium are grown as ornamental plants, in particular in Asia. Tobacco leaf curl virus is a pathogen occasionally affecting plants of this genus. The foliage is eaten by some Lepidoptera larvae, including those of Orthonama obstipata.

photo from wikipedia

photo: Hjortetrøst Sletterhage and Bjerre Skov: grethe bachmann