According to observations of naturalists and beekeepers.
Where are you?
Feltleaf willow is native to northern North America and eastern Siberia. In North America, it occurs from Alaska south to British Columbia to about 53 °N latitude, east to Québec, and north to Nunavut.
This plant is present in at least 8 states/provinces in this country.
Feltleaf willow is a tree or shrub 2 to 33 feet (0.5-10 m) tall. It typically grows in clumps of 5 to 20 stems. Branches are typically erect, but in exposed High Arctic and alpine sites feltleaf willow may have a prostrate or semiprostrate form. Trunks maybe 4 to 7 inches (10-18 cm) in diameter. Heavy browsing commonly hedges feltleaf willows.
Leaves are deciduous, alternate, and simple. They are 2.0 to 4.3 inches (5-11 cm) long and 0.4 to 1.6 inches (1-4 cm) wide.
The inflorescence is a catkin. Male catkins are 1.2 to 2.0 inches (3-5 cm) long, and female catkins are 2.0 to 5.9 (5-15 cm) long. The fruit is a capsule, which splits open to release the seeds. A tuft of hairs plumes each seed.
Willow roots are typically shallow. Feltleaf willow sometimes forms adventitious roots.
Feltleaf willow stands are open to closed. Closed feltleaf willow stands (canopy closure >75%) are characteristic of floodplains and outwash deposits, while open feltleaf willow stands (canopy closure 25%-74%) occupy a variety of sites from sand dunes to riverbanks.
Feltleaf willow catkins appear and pollination occurs in spring before leaves emerge. In Alaska, flowering and seed dispersal occur from May to July. In general, seeds are dispersed later as latitude and elevation increase. Seed dispersal often coincides with receding spring floodwaters, when newly exposed mineral soil seedbeds are moist. Feltleaf willow is often one of the first willows to disperse seeds in interior Alaska. The rate of seed dispersal in willows depends on weather. Under warm, dry, windy conditions, all seeds may be dispersed within a few days. Under wet, cool conditions, dispersal may be spread out over a month.