Salix exigua

From Wikipedia, the free encyclopedia

Salix exigua
Leaves and staminate flower
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Salicaceae
Genus: Salix
S. exigua
Binomial name
Salix exigua
Natural range of Salix exigua
S.e.exigua: green, S.e.hindsiana: blue, S.e.interior: red

Salix exigua (sandbar willow, narrowleaf willow, or coyote willow; syn. S. argophylla, S. hindsiana, S. interior, S. linearifolia, S. luteosericea, S. malacophylla, S. nevadensis, and S. parishiana) is a species of willow native to most of North America except for the southeast and far north, occurring from Alaska east to New Brunswick, and south to northern Mexico.[2] It is considered a threatened species in Massachusetts while in Connecticut, Maryland, and New Hampshire it is considered endangered.[3]


It is a deciduous shrub reaching 4–7 metres (13–23 ft) in height, exceptionally 7.6 m (25 ft)[4] spreading by basal shoots to form dense clonal colonies. The leaves are narrow lanceolate, 4–12 centimetres (1+124+34 in) long and 2–10 millimetres (11638 in) broad, green, to grayish with silky white hairs at least when young; the margin is entire or with a few irregular, widely spaced small teeth. The flowers are produced in catkins in late spring, after the leaves appear. It is dioecious, with staminate and pistillate catkins on separate plants, the male catkins up to 10 cm (4 in) long, the female catkins up to 8 cm (3 in) long. The fruit is a cluster of capsules, each containing numerous minute seeds embedded in shiny white silk.[5][6]

Subspecies and Variants[edit]

The two subspecies, which meet in the western Great Plains, are:[2][5]

  • S. exigua subsp. exigua – western North America, leaves grayish all summer with persistent silky hairs, seed capsules 3–6 millimetres (0.12–0.24 in) long
  • S. exigua subsp. interior (Rowlee) Cronq. (syn. S. interior Rowlee) – eastern and central North America, leaves usually lose hairs and become green by summer, only rarely remaining pubescent, seed capsules 5–8 millimetres (0.20–0.31 in) long

In California and Oregon,

  • S. exigua var. hindsiana – Hinds' willow[7][8]


Salix exigua is cultivated as an ornamental tree. In the UK it has gained the Royal Horticultural Society's Award of Garden Merit.[9][10]


This willow has many uses for Native Americans; the branches are used as flexible poles and building materials, the smaller twigs are used to make baskets, the bark is made into cord and string, and the bark and leaves have several medicinal uses.[11] The Zuni people take an infusion of the bark for coughs and sore throats.[12]

The foliage is browsed by livestock.[13]


The male flowers provide pollen for bees. It is a larval host to the California hairstreak, Lorquin's admiral, mourning cloak, sylvan hairstreak, and tiger swallowtail.[14]


  1. ^ Stritch, L. (2020). "Salix exigua (amended version of 2018 assessment)". IUCN Red List of Threatened Species. 2020: e.T126589236A174155123. doi:10.2305/IUCN.UK.2020-2.RLTS.T126589236A174155123.en. Retrieved 11 April 2024.
  2. ^ a b Lesica, Peter (30 June 2012). Manual of Montana Vascular Plants. BRIT Press. ISBN 978-1-889878-39-3.
  3. ^ Salix exigua Retrieved 24 April 2019.
  4. ^ Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. p. 191. ISBN 978-1-68051-329-5. OCLC 1141235469.
  5. ^ a b Northern Prairie Wildlife Research Center: Salix exigua Archived 2008-03-28 at the Wayback Machine
  6. ^ Jepson Flora: Salix exigua
  7. ^ "Salix exigua var. hindsiana". Integrated Taxonomic Information System. Retrieved 29 April 2022.
  8. ^ "Salix exigua var. exigua". Integrated Taxonomic Information System. Retrieved 29 April 2022.
  9. ^ "RHS Plantfinder - Salix exigua". Retrieved 24 April 2019.
  10. ^ "AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 93. Retrieved 24 April 2019.
  11. ^ University of Michigan Native American Ethnobotany Index:Salix exigua
  12. ^ Camazine, Scott and Robert A. Bye 1980 A Study Of The Medical Ethnobotany Of The Zuni Indians of New Mexico. Journal of Ethnopharmacology 2:365–388 (p. 378)
  13. ^ Little, Elbert L. (1980). The Audubon Society Field Guide to North American Trees: Eastern Region. New York: Knopf. p. 333. ISBN 0-394-50760-6.
  14. ^ The Xerces Society (2016), Gardening for Butterflies: How You Can Attract and Protect Beautiful, Beneficial Insects, Timber Press.

External links[edit]