The genus Salix, as recognised in 2019, is comprised of probably more than 300 distinct species (over 500 if you also accept hybrid species). Many of these species are very similar, sometimes being separated as much by native range as by any other characteristic. Hybridization between species is common, when this is coupled with the high genetic and morphological variability within many species, and different levels of ploidy, the complexity of this genus is clear.
Misidentification of specimens is not rare, even amongst botanists, and many records of plant use will often equally apply to one or more related species that were not seen as distinct when the report was made. Equally, several species not included in the database will be found to have a range of these uses. In general, all species in the genus have medicinal uses, especially as antiinflammatories, analgesics and febrifuges, they can all serve as emergency foods, many of them have flexible stems and can be used in basket making, and many of them can be planted in moist to wet conditions in order to stabilize the soil and improve wildlife habitats.

Common Name: Purple Osier

General Information

Salix purpurea is a graceful, slender-stemmed, deciduous shrub or occasionally a small tree that can grow up to 10 metres tall, though is more commonly within the range 1 - 4 metres[, ].
The plant is harvested from the wild for local use as a food, medicine and source of materials. It produces excellent quality stems for basket making and has a long history of cultivation for this purpose, there are several named forms. It is also planted on banks to stabilize the soil, and is grown as an ornamental, where it can be used as a hedge.
Salix purpurea has a widespread distribution, stable populations and no major threats. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2017)[].

Known Hazards

None known

Botanical References

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Range

Europe - Britain to Spain, east to southern Russia, Ukraine and the Balkans; N. Africa - Morocco, Algeria, Tunisia

Habitat

Wet places in lowland areas[, ], preferring neutral or alkaline soils[]. Shores, canals, wet meadows, coppices, and sands[].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	5.00 m
Growth Rate	Fast
Pollinators	Bees, Insects
Self-fertile	No
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Salix purpurea is a very cold-hardy plant, able to tolerate temperatures down to around -25°c when fully dormant[].
Salix species generally require an open position and abhor dryness at the roots. Whilst many can be found in wet or boggy soils, and prefer a damp, heavy soil, most will grow well in a range of moist but well-drained soils so long as they are fairly deep. Very few are at home in chalky soils[, , ]. This species prefers an alkaline or neutral soil, rarely doing well in acid conditions[]. It is said to prefer a sandy soil[, ], and is more tolerant of dryish soils than most willows[]. Plants are tolerant of salt water[].
A very ornamental plant[], it is also cultivated for its branches which are used in basket making and for bioenergy[, ], there are some named varieties[].
Plants can be coppiced annually[]
Plants can live around 30 years[].
The flowers are dioecious, male and female flowers being produced on separate plants. If seed is required then at least one plant of each sex need to be growing in reasonable proximity[].
Hybridization in the genus is common, especially when species are brought together in cultivation[].
Salix species are unusual in as much as, although they produce their flowers in catkins, these are insect rather than wind pollinated. Indeed, the flowers of many species are excellent sources of nectar for bees and other insects, especially valuable are those species that flower early in the growing season[].
The roots of Salix species are often vigorous and extensive and can range some distance from the plant. Several species are known to cause problems by growing into drains and drainage systems as their roots seek out moisture[].
Species in this genus are often notably susceptible to honey fungus[].

Edible Uses

Growing in harsh and difficult environments, as many willows do (they can be found within the arctic circle, on mountains and even in the desert), Salix species have often been utilized as an emergency food source. They are, indeed, often a highly favoured food source for birds and mammals and, whilst few species would lay claim to culinary excellence for humans, the young shoots and inner bark are both edible eaten either raw or cooked[].
We have no specific information for this species, but the inner bark can be eaten fresh or it can be dried, ground into a powder and then added to cereal flour for use in making bread etc. It has a very bitter flavour, The young shoots are also somewhat bitter and not very appetizing - unless you are really hungry of course![].

Medicinal

The bark is anodyne, anti-inflammatory, antiperiodic, antiseptic, astringent, diaphoretic, diuretic, febrifuge, hypnotic, sedative and tonic[, , ]. It is a very rich source of salicin, which is used in making aspirin[]. The bark of this species is used interchangeably with Salix alba. It is taken internally in the treatment of rheumatism, arthritis, gout, inflammatory stages of auto-immune diseases, diarrhoea, dysentery, feverish illnesses, neuralgia and headache[]. The bark is removed during the summer and dried for later use[].

The leaves are used internally in the treatment of minor feverish illnesses and colic[], cancerous sores and chronic dysentery[]. The leaves can be harvested throughout the growing season and are used fresh or dried[].

The twigs are used in the treatment of cancer, dysentery and ulcers[].

The bark of the stem and roots is anodyne and styptic[]. It is used in the treatment of rheumatism[].

The bark of this willow is used in preference to other species for salicin extraction (content 0.6 - 1.5%)[].
Repeated selection and trials in Europe for the medicinal use of the bark and the leaves as an analgetic and febrifuge, applicated in phytotherapy instead of synthetic salicylic acid, which had widely replaced salicin, formerly extracted from the bark of this and some other Salix spp[].

Agroforestry Uses:

Plants can be grown as a hedge[], the var. 'Gracilis' is suitable for a small hedge on damp sites[, ]. It can be kept dense by annual clipping[].
The plant is grown in N. America as a bioenergy crop, being coppiced annually for this purpose[].
The plant has an extensive root system and is used in soil reclamation and stabilization projects along estuaries[].
The bark has a very bitter flavour due to its high content of salicin. It is much disliked by rabbits, so a closely woven fence of this plant can be used as a protective barrier[].
Purple osier is an excellent pioneer forest species in moist soils. It has light seeds that can be blown for long distances in the wind and germinate in open situations. It grows rapidly, quickly establishing suitable conditions for other forest trees to become established and thrive. It is also short-lived and shade-intolerant, so tends to die out after about 30 years and make space for the climax forest trees[, ].
A very important food plant for the caterpillars of many butterfly species[] and a good bee plant, providing an early source of nectar and pollen[].

Other Uses

The stems are very tough and flexible and are used in basket making[, , , ]. Particularly valued for basketry due to fineness, flexibility, and whiteness of the straight smooth lustrous twigs, called "basket hair," and amenable to wickerwork[]. The plant is usually coppiced annually when grown for basket making, though it is possible to coppice it every two years if thick poles are required as uprights.

Also used as a dyeing plant[].

The bark contains about 10% tannin[].

An extract of the bark is used as an ingredient in commercial cosmetic preparations as a skin conditioner[].

The wood of larger specimens is utilized[].

Propagation

Willow seed is very small and light, and has a very short viability, perhaps as little as a few days in some species. It must be surface sown as soon as it is ripe. In nature the seed only germinates in disturbed soils in an open situation. In nursery conditions, sow the seed in a tray in a moderately sunny position and keep the soil moist. Germination is usually quite rapid - prick out the seedlings into individual pots when they are large enough to handle and grow on until large enough to plant out. Plants generally establish better if planted out whilst quite small.
Cuttings of mature wood of the current year's growth or older can root at almost any time of the year, though late autumn is considered best as this produces a better balance of root and stem growth the following spring[]. Plant them in a sheltered outdoor nursery bed or straight into their permanent position and give them a good weed-suppressing mulch. Most species are very easy. Plant into their permanent positions in the following autumn.
Cuttings of half-ripe wood, early to mid summer in a frame. Very easy.