The North Creek Wetland

Sitka willow

Salix sitchensis – Sitka willow

At a Glance:

  • Family: Salicaceae
  • Plant Type: large spreading multi-stemmed shrub/tree
  • Distribution: Pacific Coast, California to Alaska, as far east as Montana
  • Habitat: Moist woods, along rivers and streams, and wetlands
  • Height: 6-20 feet tall
  • Flowers/Fruits: drooping catkins. Males catkins are green/yellow, females are pale green. Once fruits develop, seeds are dispersed in the wind with fine, silky hairs (like cottonwood).
  • Flowering Season: April – June
  • Leaves: green, smooth upper surface, with a lighter green/white, very hairy, velvety underside. Leaf shapes are generally spatulate/oblanceolate with a pointed tip.
  • Generation: Perennial
  • Bark: smooth and slightly furrowed and scaly
  • Notable feature: Pacific willow responds well to herbivory and fire, especially when beavers chew them down. After their main trunk is cut down, the tree will send up many trunks and become a multi-stemmed shrub.

Restoration and Conservation

Sitka willow leaves provide browse for deer, American beavers, elk, moose, bears and small mammals. It provides habitat as a large dense shrub for birds and small mammals to shelter within. Beavers build dens and dams from the branches. Birds eat the willow buds, leaves, twigs and seeds. Sitka willow grows well along stream banks and in wetlands, helping with soil stabilization, providing shade to cool down water temperatures, and providing woody debris into the water creating ideal fish and salmon habitats. The decaying leaves over winter provide nutrients for the aquatic bacteria improving the aquatic food chain.

The bark and roots of our three campus willows assist other plants in establishing by acting as a rooting hormone.

Ethnobotany

Northwest native tribes used the branches and twigs to make a variety of household and fishing tools. The Snohomish tribe made a two-ply string/cord from the pounded down bark. Willow bark is high in salicylic acid, the active ingredient in aspirin. Before aspirin was commercially made in a lab, willow bark was the main source for pain relief.

The early floral buds are soft and velvety. They are called “pussy willows” and are harvested for the floral industry.

References and Resources

This article was written by Sarah Verlinde. For questions regarding the UWB/CC Plant Tour, contact Sarah at severlin@uw.edu.