- Name also: Meadow Pea, Meadow Pea-vine
- Family: Pea Family – Fabaceae (Leguminosae)
- Growing form: Perennial herb.
- Height: 25–60 cm (10–25 in.). Stem limp, climbing, bristly, wingless, usually hairy.
- Flower: Corolla irregular (zygomorphic), yellow, 10–16 mm (0.4–0.64 in.) long, long, fused at base. 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. Stamens 10. A single carpel. Inflorescence long-stalked, 5–12-flowered raceme.
- Leaves: Alternate, stalked, stipulate. Blade 1-pairs, terminal leaflet modified into a tendril. Leaflets lanceolate, tapered, with entire margins. Stipules large.
- Fruit: 20–40 mm (0.8–1.6 in.) long, black pod.
- Habitat: Meadows, pastures, hay-fields, banks, waste ground, forest margins, herbaceous forests, waterside hedgerows, sea-shores.
- Flowering time: June–August.
Meadow vetchling’s Finnish names often involve animals, and in the past it has been dedicated to mice, rats, dogs and hares, not to mention birds and grasshoppers. Other old names emphasise what is perhaps its most apparent quality: its glowing yellow flowers.
Despite its many names, meadow vetchling has never been an important nutritional or medicinal plant, although it has probably been a useful fodder plant. Its many names probably mean that it has been common and visible. Meadow vetchling spreads widely through its runner-like rhizome to form large stands. Sexual propagation is however problematic: pods don’t develop on most of the flowers and the seeds are prone to being destroyed by insects. It makes an impressive sight however when it is in bloom, and it stands out easily among the surrounding grasses. It climbs up to become visible by using its tendrils to climb on other plants. It has only one pair of real leaflets, but at its base is a pair of stipules that increase its assimilation surface and which are not smaller than real leaflets.
Meadow vetchling is the only yellow-flowered species out of the members of its genus that are established in Finland. At first glance its flowers might look like bird’s-foot trefoil (Lotus corniculatus), but the latter has a tendril instead of a terminal leaflet, and it doesn’t use other plants to climb on.