According to observations of naturalists and beekeepers.
Where are you?
Littletree willow occurs in central Alaska, the Yukon Territory, and adjacent Northwest Territories eastward throughout the boreal forest to Hudson Bay. It extends southward in the eastern Rocky Mountains to northeastern British Columbia, northern Alberta, Saskatchewan, and Manitoba. Littletree willow does not occur in the contiguous United States.
This plant is present in at least 10 states/provinces in this country.
Acer saccharinum (aka: Silver maple, Soft maple)
Aronia arbutifolia (aka: Red chokeberry)
Acer negundo (aka: Boxelder, Western boxelder, Arizona boxelder, California boxelder, Texas boxelder, Interior boxelder, Violet boxelder)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Ulmus americana (aka: American elm, White elm, Water elm, Soft elm, Florida elm)
Salix discolor (aka: Pussy willow, American pussy willow, Glaucous willow, Large pussy willow)
Salix amygdaloides (aka: Peachleaf willow, Peach leaf willow)
Amelanchier arborea (aka: Common serviceberry, Downy serviceberry, Juneberry, Shadbush, Shadblow, Sugarplum)
Acer saccharum (aka: Sugar maple, Rock maple, Hard maple)
Crataegus douglasii (aka: Black hawthorn, Douglas hawthorn, River hawthorn, Western thornapple)
Prunus cerasus (aka: Sour cherry, Tart cherry, Dwarf cherry, Montmorency cherry)
Populus tremuloides (aka: Quaking aspen, Trembling aspen, Aspen, American aspen, Mountain aspen, Golden aspen, Trembling poplar, White poplar, Popple, Alamo Blanco)
Prunus pumila (aka: Sandcherry, Western sandcherry, Eastern sandcherry, Great Lakes sandcherry)
Salix arbusculoides (aka: Littletree willow)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Acer rubrum (aka: Red maple, Scarlet maple)
Malus domestica (aka: Pyrus pumila, Malus pumila, Apple)
Acer platanoides (aka: Norway maple)
Prunus americana (aka: American plum, Goose plum, River plum, Wild plum)