Common Name: Hairy Tare

General Information

Vicia hirsuta is a climbing, annual plant producing stems 20 - 140cm long that scramble over the ground and climb into other plants for support[, , ].
The plant is sometimes harvested from the wild for local use as a food. It has occasionally been cultivated for its edible seed, which is used as a lentil substitute[].
The plant is considered a weed in many countries[, ].

Known Hazards

The seeds contain the anti-nutritional compound L-canavanine, a competitive inhibitor of arginine decarboxylase. This is removed by soaking the seeds in water prior to cooking and discarding the soak water.
The seeds contain trypsin inhibitors. Soaking them before cooking, perhaps even allowing them to sprout a little, and the cooking process itself, all serve to reduce the amount of trypsin inhibitors[, ].
The seeds also contain the non-protein amino acid canavanine, a toxic arginine analogue[]

Botanical References

, ,

Range

Eurasia - Norway to Portugal, east to Siberia, China, Japan, Korea, northern India; Africa - Morocco to Egypt and Ethiopia, Uganda, Kenya, Tanzania,

Habitat

A common weed of cultivation, avoiding acid soils[]. Valleys, grassy slopes, grasslands, creek banks, along streams, farms, fields and field margins, villages, gardens, cultivated areas, roadsides; at elevations from sea level to 2,900 metres[].

Properties

Weed Potential	Yes
Edibility Rating
Habit	Annual Climber
Height	0.45 m
Pollinators	Bees, Lepidoptera, Self
Self-fertile	Yes
Cultivation Status	Cultivated, Wild

Cultivation Details

Hairy tare is native from the cooler temperate zone of north Europe, through the subtropics to moderate and higher elevations in the tropics.
Succeeds in any well-drained soil in a sunny position if the soil is reliably moist throughout the growing season, otherwise it is best grown in semi-shade[].
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[]. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen.

Edible Uses

Seed - cooked[, , ]. Mainly seen as a famine food, for use when nothing better is available, though they can be used like lentils[], and are sometimes eaten as a staple food[]. The seed is 1.5 - 3mm in diameter[]. The seed should be soaked prior to cooking in a solution of sodium carbonate[]..

Leaves and stems - cooked[, , ]. Used as a vegetable[].

Medicinal

None known

Other Uses

None known

Propagation

Seed - sow in situ in spring or autumn. The seed has a hard seedcoat and may benefit 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.