Salix / Willow
Common Name: Willow
Willow blossoms provide an important early pollen source for many spring bees, including new bumble bee queens and many species of mining bees. Willows occur naturally in riparian areas, such as the banks of streams and ponds, low woods and prairie sloughs. Willow bark tea contains salicylic acid, which derives its name from Salix and forms the chemical basis of modern aspirin, and has long been used as an effective remedy for pain and fever reduction. A number of native willow species are routinely available in nurseries but avoid horticultural hybrids that produce little in the way of pollen.
Nationwide, the United States and Canada
Commercially available and can be grown in most parts of North America, under adequately moist conditions
Full sun to partial shade
Wet to average
Salix discolor (pussy willow) is a shrub or small tree that grows to about 20 feet. Its native range extends throughout Canada, the Midwest and the Northeast United States. The familiar, silvery-gray, furry catkins, which appear before leaf emergence, are recognized as one of the first signs of spring. This plant attracts many spring bees and butterflies and is a larval host for mourning cloak and viceroy. It requires fairly moist conditions and is routinely available in North American nurseries.
Salix nigra (black willow) is a small to medium-sized tree 30 to 60 feet high, native to the eastern United States and Canada. The flowers of black willow are either male or female yellow catkins, which occur on separate trees. It is therefore best to select male trees for the purpose of providing a pollen source for bees. Black willow is adapted wherever ample soil moisture is found. It can be planted as an ornamental and used as a shade tree. It will tolerate dry soils, but with reduced vigor. It is commercially available and easily established from cuttings.
Salix amygdaloides (peachleaf willow) is a native species found in many riparian ecosystems throughout the American West and Midwest, as well as southern Canada. It can be found on the northern prairies, often near streams and accompanying cottonwoods. In its native range, peachleaf willow provides forage and shelter for birds and small mammals and serves as a larval host for mourning cloak and viceroy butterflies. This small to medium sized tree (up to 40 feet) produces yellow flowers or catkins in spring, which are a good pollen and nectar source for bees. The leaves resemble peach leaves, hence the name, peachleaf willow. It requires moist soil and is commercially available.
Salix cinerea (large gray willow) is an introduced species throughout the eastern United States. Though not a native willow, it provides a good pollen source for spring bees and is routinely available in nurseries.