White Snakeroot, Richweed
Ageratina altissima

Family: Asteraceae or Compositae

What it is like

Ageratina altissima is a PERENNIAL growing to 2 m (6ft 7in). See above for USDA hardiness. It is hardy to UK zone 6. It is in flower from August to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 2

Where it is found

Low woods in river valleys in Texas.

Eastern N. America.

Conservation Status: This taxon has not yet been assessed.

Countries/locations it is found in

How it is used

Food

Rating: 0

Medicine

Rating: 2

The root is 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. The root has been chewed and held in the mouth as a treatment for toothache.

Diaphoretic: Induces perspiration.

Diuretic: Acts on the kidneys, promoting the flow of urine.

Febrifuge: Reduces fevers.

Odontalgic: Treats toothache (temporary measure only) and other problems of the teeth and gums.

Stimulant: Excites or quickens activity of the physiological processes. Faster acting than a tonic but differing from a narcotic in that it does not give a false sense of well-being.

Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.

Urinary: Treats urinary problems, including urinary tract infection (UTI).

Other

Rating: 0

How it is grown

Succeeds in an ordinary well-drained but moisture retentive garden soil in sun or part shade. There is some difference of opinion over the correct name for this species with some authorities using Eupatorium rugosum.

Propagating it: 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.

Best place to grow: Woodland Garden Sunny Edge; Dappled Shade;

Habit: Perennial

Hardiness: 5-9

Growth:

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

The plant contains tremetol, a complex alcohol, and glycosides. 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.

Its other names

Local names

Synonyms

Eupatorium ageratoides. E. rugosum. E. urticaefolium,