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Willow

Willow refers to deciduous trees and shrubs in the genus Salix, in the willow family Salicaceae.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 27, 2026|2 min read| Fact-checked

Willows are deciduous trees and shrubs in the genus Salix, part of the willow family Salicaceae. They are known for their narrow leaves, catkins, and preference for moist habitats, and many species are used for ornament, erosion control, and basketry. Willows are widely distributed in cold and temperate regions of the Northern Hemisphere, especially near water sources.

Description

Willows are mostly deciduous trees and shrubs with alternate leaves that are usually narrow, though leaf shape varies across species. They are recognized by their catkins and by the fact that male and female flowers are on separate plants.

Distribution and habitat

The genus is native mainly to north temperate regions and is strongly associated with moist soils. Some species extend into the Arctic, while others are widely cultivated beyond their native range. In their natural habitat, willows are often found alongside other deciduous trees such as oak and maple, as well as conifers like spruce.

Uses

Willows are valued in horticulture and land management for their fast growth, ornamental form, and ability to help stabilize soil. Their flexible stems are also used in wickerwork and other crafts, and some species contain salicin, historically used as a pain reliever. They are planted for ornament, shade, shelterbelts, and erosion control.

Species diversity

Salix is a diverse genus with roughly 350 species according to some references, and counts vary by source because of hybrids and differing taxonomic treatments. Common names such as osier and sallow are applied to some groups of willows.

Willows in Canada

Willows are native and widely distributed in Canada, with about 54 native species reported and several reaching tree size. They have been used in Canadian shelterbelts, ornamentals, erosion control, and traditional medicinal and craft uses.

Key facts

  • Willows are plants in the genus Salix, which includes hundreds of species and many hybrids.
  • They are typically found in moist habitats, especially in temperate and colder regions of the Northern Hemisphere.
  • Willows are dioecious, meaning male and female flowers usually occur on separate plants.
  • Willow wood and branches have long been used for basketry, weaving, and rustic furniture.
  • Some species contain salicin, historically used as a pain reliever.
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Canadian context

Willows are native and widely distributed in Canada, with about 54 native species reported and several reaching tree size. They have also been used in Canadian shelterbelts, ornamentals, erosion control, and traditional medicinal and craft uses.

Frequently asked questions

What is a willow?
A willow is a deciduous tree or shrub in the genus Salix, in the family Salicaceae.
Where do willows grow?
Willows grow mainly in moist soils in temperate and colder regions, often near rivers, wetlands, and other water sources.
Why are willow trees useful?
They are planted for ornament, shade, shelterbelts, and erosion control, and their flexible stems are used in basketry and weaving.
Are willow flowers and leaves on the same plant?
No. Willows are dioecious, so male and female flowers usually occur on separate plants.
What are willow flowers like?
Willow flowers are borne in catkins, which are often visible before the leaves emerge.
How many willow species are there?
Sources commonly cite about 350 species, though the exact number varies with taxonomic treatment and the presence of hybrids.

References

  1. Encyclopaedia Britannica — https://www.britannica.com/plant/willow
    Supports: Genus Salix; family Salicaceae; habitat; catkins; dioecious flowers; uses; salicin
  2. The Canadian Encyclopedia — https://thecanadianencyclopedia.ca/en/article/willow
    Supports: Canadian native species count; distribution in Canada; uses in shelterbelts, erosion control, basketry, and traditional medicinal uses
  3. Royal Horticultural Society — https://www.rhs.org.uk/plants/willow/trees
    Supports: General cultivation traits, moist soil preference, early spring catkins, and weeping willow form
  4. Wikipedia — https://en.wikipedia.org/wiki/Willow
    Supports: Approximate species count and common names such as sallow and osier