Common Name: White Snakeroot

General Information

Ageratina altissima is an erect, herbaceous perennial plant producing a cluster of branched stems from a usually fibrous-rooted crown, though it is sometimes rhizomatous. It usually grows 50 - 80cm tall, but can grow up to 120cm[, ].
The plant has been harvested from the wild for local use as a medicine. It is sometimes grown in ornamental gardens and there is at least one named cultivar.
This is a somewhat weedy perennial that can spread aggressively by rhizomes and self-seeding[].

Known Hazards

The plant contains tremetol, glycosides and a complex alcohol. These toxins cause a fatal disease known as 'staggers' in cattle. The toxin can be passed through the milk and has caused fatalities in humans who have drunk affected cow's milk[, ].

Botanical References

, ,

Range

Eastern and central N. America - Saskatchewan to New Brunswick, south to Texas and Florida.

Habitat

Low woods in river valleys in Texas[]. Moist forests, cove forests at elevations of 10 - 800 metres[]

Properties

Weed Potential	Yes
Medicinal Rating
Habit	Perennial
Height	0.75 m
Pollinators	Insects
Self-fertile	Yes
Cultivation Status	Ornamental, Wild

Cultivation Details

An easily grown plant, succeeding in an ordinary well-drained but moisture retentive garden soil in sun or part shade[, ]. It prefers part shade in moist, humus-rich soils, although it also does reasonably well in dryish soils[]. These plants have decidedly better shade tolerance than most other species in the genus[]
The flowers are very attractive to butterflies[].
Probably hybridizes in the wild with Ageratina aromatica[].

Edible Uses

None known

Medicinal

This plant should be used with caution - see the notes above on toxicity.
The root is antidote, diaphoretic, diuretic, febrifuge, stimulant and tonic[]. It has been used in the treatment of diarrhoea, gravel and urinary diseases[]. It has also been used in herbal sweat baths to encourage sweating[]. A decoction or infusion of the root has been taken to treat a fallen or inflamed womb[]. A decoction of the roots has been used as a remedy for snakebite[].
The root has been chewed and held in the mouth as a treatment for toothache[].

Other Uses

None known

Propagation

Seed - sow spring in a cold frame, only just covering the seed. When large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.
Division in spring.