Common Name: Alpine Sweetvetch

General Information

Hedysarum alpinum is a herbaceous perennial plant with numerous, erect stems growing from a thickened, elongate rootstock; it can grow 40 - 120cm tall[, ]. The plant spreads by means of rhizomes. Mature plants may have roots with multiple branches that are several feet long and 'as thick as a carrot'[].
The plant is harvested from the wild for local use as a food. The roots were an important food source for the native Alaskans and are still utilized by modern-day tribes[]. This is one of several Hedysarum species that have a long history of medicinal use in Chinese traditional medicine. It is harvested from the wild and traded in local markets. The plant is used in soil rehabilitation projects. The plant is the main source of the pharmaceutical drug 'alpizarin', an antiviral agent used in the treatment of herpes and other conditions[].
The species is widespread and while it is possibly declining in parts of its range, it is not thought that any global population decline is likely to meet (or be close to meeting) the threshold for Vulnerable. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

None known

Botanical References

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Range

Eurasia - northern European Russia east to Mongolia, the Russian Far East, northern China, Korea; N. America - Wyoming to New Hampshire an northwards

Habitat

Calcareous rocks and gravelly soils, north to Alaska[]. Swampy meadows, taiga forests, stony slopes, scrub[]. Forest meadows, birch and pine forests, slopes and bluff shores[].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	0.60 m
Pollinators	Bees, Insects
Cultivation Status	Wild

Cultivation Details

Hedysarum alpinum is primarily a plant of boreal or northern temperate climates where day lengths can range from periods of permanent dark in winter to 24 hours of light in the summer. It can tolerate very low temperatures - in some parts of its range the winter temperatures average -12°c, with absolute lows considerably lower. Summers are cool, often averaging no more than 12°c. The climate can be dry, as low as 119mm in some areas, whilst 711mm in just 48 hours has also been recorded[].
Prefers a sunny position, but also succeeds in light shade[]. Easily grown in ordinary garden soil, preferring a deep well-drained sandy loam[, ]. Plants are often found on dry to moist soils with a high pH in the wild[, ]. Plants are tolerant of occasional inundation of the soil[]. Plants can succeed in soils with a pH ranging from 4.5 - 8.4[].
Plants strongly resent root disturbance and should be placed in their permanent positions as soon as possible[].
The var. Hedysarum alpinum americanum. Michx. is the variety used for food[, ].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

Root - raw or cooked[, ]. Eaten raw, boiled or roasted[]. A carrot-like flavour[]. The root can be harvested from autumn until spring, it tastes best after some frosts[].

Medicinal

The areial parts of this plant are used in the pharmaceutical industry as the main source of the compound 'alpizarin', an antiviral, immunomodulatory, bacteriostatic and antibacterial agent. Alpizarin has also shown prominent cardiostimulant, capillary-strengthening, anti-inflammatory properties and enhances reparative processes in the gastric mucosa. It is used in tablet form and as an ointment to treat primary and secondary infection of the mucous membranes and skin by the herpes virus; shingles; warts etc[].

This species has a long histroy of medicinal use in China, where it is employed mainly to increase the energy of the body. It is used in the treatment of infestation with gastrointestinal nematodes, and may also support the immune system and peripheral nervous system[].

Various medicinally active compounds found in this and other Hedysarum species contribute to the antioxidant, anti-tumor, anti-aging, anti-diabetic, and anti-hypertensive properties of the plants[].

Agroforestry Uses:

The plant is used in rehabilitation projects on disturbed sites, usually growing well on subsoils and helping to restore fertility[].

Other Uses

None known

Propagation

Seed - sow in a cold frame as soon as it is ripe or in the spring[]. Stored seed benefits from scarification before sowing in order to speed up and improve germination[]. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing[]. Prick out the seedlings into individual pots as soon as they are large enough to handle and plant them out into their permanent positions in the summer.
Division in spring. Great care is needed since the plant dislikes root disturbance[].