metsäköynnös

Metsäköynnös, scientifically known as Clematis vitalba, is a vigorous deciduous climbing plant commonly found in Europe and Western Asia. It is a species of flowering plant in the buttercup family Ranunculaceae. Metsäköynnös typically grows in woodlands, hedgerows, and scrubland, often favoring calcareous soils. Its growth habit is scandent, meaning it climbs by twining around other plants or structures. The plant can reach considerable lengths, often forming dense thickets that can smother smaller vegetation.

The leaves of metsäköynnös are pinnately compound, typically with five to seven ovate or elliptic leaflets that are dark green and somewhat leathery. During summer, the plant produces abundant clusters of small, fragrant, creamy-white flowers. These flowers lack petals but possess numerous prominent stamens, which give them a fluffy appearance. Following flowering, the plant develops characteristic feathery, plumed seed heads, which persist well into winter and contribute to its common name, "old man's beard" in some regions.

While attractive, metsäköynnös is considered an invasive species in some parts of the world, including New Zealand and Australia, where it can outcompete native flora. Its rapid growth and ability to produce large quantities of seeds make it a challenging weed to control in affected areas. In its native range, it plays a role in the ecosystem, providing food and shelter for various insects and birds.