Common Name: American Bistort

General Information

Polygonum bistortoides is a herbaceous perennial plant growing from a rhizomatous rootstock; it produces a cluster of stems usually 20 - 70cm tall[].
The plant is harvested from the wild for local use as a food and medicine

Known Hazards

Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people.
Many species also contain oxalic acid (the distinctive lemony flavour of sorrel) - whilst not toxic this substance can bind up other minerals making them unavailable to the body and leading to mineral deficiency. Having said that, a number of common foods such as sorrel and rhubarb contain oxalic acid and the leaves of most members of this genus are nutritious and beneficial to eat in moderate quantities. Cooking the leaves will reduce their content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[].

Botanical References

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Range

Western N. America - British Colombia and Alberta, south to California, Arizona, New Mexico and northeast Mexico

Habitat

Streambanks, moist or swampy meadows, alpine slopes; at elevations from 1,300 - 3,800 metres[]. Moist or wet meadows and swamps, seldom below 2,500 metres[, ].

Properties

Edibility Rating
Medicinal Rating
Habit	Perennial
Height	0.45 m
Pollinators	Insects
Cultivation Status	Wild

Cultivation Details

This is a very cold-hardy plant, being able to tolerate temperatures down to around -25°c when fully dormant.
Succeeds in an ordinary garden soil[] but prefers a moisture retentive not too fertile soil in sun or part shade[]. Repays generous treatment[]. Plants are growing well at Kew in a moist position by water in the rock garden[].
Plants seem to be immune to the predations of rabbits[].
This species is closely related to P. viviparum[] and P. bistorta[].

Edible Uses

Leaves - raw or cooked. A pleasant acid flavour, they are used as a potherb[].

Root - raw or cooked[]. Starchy and rather pleasant[], the root can be baked or added to soups, stews etc[, , , ]. It was often dried before being used[]. The raw root is slightly astringent, it becomes sweeter when boiled but is best when baked[].

We have no specific information for this species, but the seed of most, if not all, members of the genus is edible both raw and cooked, and is potentially a good source of amino acids. Unfortunately the seed is also usually rather small and fiddly to utilize[].

Medicinal

The root is astringent. A poultice has been used in treating sores and boils[].

Other Uses

None known

Propagation

Seed - sow spring in a cold frame. Germination is usually free and easy. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer if they have reached sufficient size. If not, overwinter them in a cold frame and plant them out the following spring after the last expected frosts.
Division in spring or autumn. Very easy, larger divisions can be planted out direct into their permanent positions. We have found that it is better to pot up the smaller divisions and grow them on in light shade in a cold frame until they are well established before planting them out in late spring or early summer.