According to observations of naturalists and beekeepers.
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Diamondleaf willow grows from the southern Yukon Territory south to California and New Mexico, and east across boreal Canada to eastern Canada and New England. It is restricted to mountainous terrain in the western United States.
This plant is present in at least 29 states/provinces in this country.
Diamondleaf willow is a small-to-medium-sized deciduous shrub. The bark is gray and smooth. The flowers occur in about 1- to 2-inch-long (2.5 cm), erect catkins on the previous year's twigs.
Diamondleaf willow flowers appear in the spring before or sometimes with the leaves.
Acer saccharinum (aka: Silver maple, Soft maple)
Cercis canadensis (aka: Eastern redbud, Redbud, Cersis Reniformis)
Salix gooddingii (aka: Goodding's willow, Dudley willow, Valley willow, Western black willow)
Prunus serotina (aka: Black cherry, Wild black cherry, Rum cherry, Mountain black cherry, Wild cherry)
Celtis laevigata (aka: Hackberry, Sugarberry, Lowland hackberry, Sugar hackberry, Arizona sugarberry, Netleaf hackberry, Small's hackberry, Southern hackberry, Texas sugarberry)
Pyrus communis (aka: European pear, Common pear)
Acer negundo (aka: Boxelder, Western boxelder, Arizona boxelder, California boxelder, Texas boxelder, Interior boxelder, Violet boxelder)
Ungnadia speciosa (aka: Mexican buckeye, Texas buckeye, Canyon buckeye, Spanish buckeye, New Mexican buckeye, New Mexico buckeye, False buckeye, Monillo, Monilla)
Acer glabrum (aka: Rocky Mountain maple, Douglas maple, Greene's maple, New Mexico maple, Torrey maple)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)