- Name also: American milk-vetch
- Family: Pea family – Fabaceae (Leguminosae)
- Growing form: Perennial herb. Rootstock thick, woody, horizontal, with short runners.
- Height: 10–40 cm (4–16 in.). Stem erect, slightly bristly.
- Flower: Corolla zygomorphic, pale yellow, 12–15 mm (0.48–0.6 in.) long. Petals 5; the upstanding the ‘standard’, the lateral two the ‘wings’, the lower two united to form the ‘keel’, overall shape of corolla being butterfly-like. Calyx 5-lobed, lobes short, triangular, black-haired. Stamens 10, filaments fused at base. A single carpel. Inflorescence a short, axillary, long-stalked, 5–20-flowered raceme.
- Leaves: Alternate, stalked, stipulate. Blade pinnate, 3–7-paired, with terminal leaflet. Leaflets elongated elliptic–ovate, blunt, with entire margins, almost glabrous. Stipules separate.
- Fruit: 1–1.5 cm (0.4–0.6 in.) long, tapering tip, black-haired, unilocular, 4–8-seeded, pendant pod (legume).
- Habitat: Grovelike forests, stream banks, waterside thickets, meadows. Calciphile.
- Flowering time: July–August.
Genus Astragalus is comprised of approximately 2,000 species and has a wide spectrum of characteristics. In northern Finland the plant enthusiast can find members of the genus with relative ease: Arctic milkvetch and alpine milkvetch (A. alpinus) look so distinctive that there is no way that they can be mixed up. At first glance it is difficult to believe that they belong to the same genus, and in this way they are a good example of the different development lines that run through this large genus. Broad beans, which are familiar from vegetable gardens, resemble the Arctic milkvetch, which is a demanding northern species that grows in broad-leaved forests, along river banks and in meadows in mountain birch woodland and forest margins. On the large fells of Enontekiö it climbs fellsides up to the lower regions of the tundra belt. Arctic milkvetch’s official species name frigidus means cold and refers to the plant’s northern and mountain habitat. From its northern homelands it sometimes travels south along rivers and like many other fell species it can also be found in the canyons of Kuusamo.
A third member of the genus liquorice milkvetch (A. glycyphyllos), which is extremely threatened, grows very rarely in south-west Finland. Both the common and scientific names obviously come form the species’ natural aroma. The leaves taste clearly like liquorice, even if the flavouring in factory-made liquorice usually come from sweet liquorice (Glycyrrhiza glabra), which also belongs to the Pea family. Liquorice milkvetch is like Arctic milkvetch in many ways, but it differs in its limp way of growing and its erect, glabrous pod. Usually the place that is found growing helps a lot with identifying the correct species. Besides these tree Astragalus species, two more are possible in Finland, both of them rare casual visitors in southern part of the country; wild lentil (A. cicer) and sand milkvetch (A. arenarius).