Willow, osier (Salix viminalis)
Common osier is a species of willow and is a deciduous broadleaf tree native to the UK, Europe and western Asia.
Common name: osier, common osier, basket willow
Scientific name: Salix viminalis
UK provenance: native
Interesting fact: more than 60 different kinds of osier hybrids and cultivated varieties are grown in Britain for the basket-making industry.
What does osier look like?
Overview: mature trees grow to 7m. The bark is greyish brown with vertical cracks. Twigs are smooth and yellow-green.
Leaves: the leaves are very long and thin (20cm by 1cm), glossy and dark green with a felt-like covering of silvery hairs beneath.
Flowers: the osier is dioecious, meaning male and female flowers are found on separate plants. Flowers are greenish catkins, which appear in late-winter to early spring before the leaves. Male catkins are yellow.
Fruits: once pollinated, the greenish female catkins develop fruit capsules, which split open when mature to release tiny seeds.
Look out for: the edges of the very narrow leaves often appear to be rolled inwards. Catkins appear before the leaves.
Could be confused with: other willow species which all freely hybridise.
Identified in winter by: the green sparsely hairy narrow buds are pressed close to the twig.
Where to find osier
It is often found growing in wet or damp situations, such as beside rivers and streams.
Value to wildlife
Caterpillars of a number of moth species feed on the foliage, including the lackey, herald and red-tipped clearwing. The catkins provide an important source of early nectar and pollen for bees and other insects, and the branches make good nesting and roosting sites for birds.
Mythology and symbolism
There is little folklore associated with osier. However, there is a local custom in Chediston, Suffolk, known as a 'willow stripping' ceremony. This is usually held at the first full moon in May. A Green George figure is dressed in willow strippings, dances around and is then ceremoniously thrown into the local pond.
How we use osier
Osier withies (strong, flexible willow stems) are traditionally used for basket-making and weaving, and are becoming increasingly popular for use as willow screens and sculptures. Osier, like all willows, is also grown for its ability to absorb heavy metals, and is often planted to 'clean up' contaminated waste ground.
Osier may be susceptible to watermark disease.