According to observations of naturalists and beekeepers.
Where are you?
Black willow is found throughout the eastern United States, adjacent parts of Canada, and Mexico. Its range extends west from southern New Brunswick and central Maine to Quebec, southern Ontario, central Michigan, southeastern Minnesota, and eastern North Dakota. It occurs south and west to the Rio Grande just below its confluence with the Pecos River; and east along the Gulf Coast through the Florida Panhandle and southern Georgia. Black willow has been introduced in Utah where it is now common along many stream bottoms.
This plant is present in at least 41 states/provinces in this country.
Black willow flowering begins in February in the southern portion of its range and extends through late June at the northern limits. The catkins usually appear at the time of or immediately preceding leaf emergence. Seeds ripen and fall in April to July.
Cercis canadensis (aka: Eastern redbud, Redbud, Cersis Reniformis)
Aronia arbutifolia (aka: Red chokeberry)
Acer saccharinum (aka: Silver maple, Soft maple)
Salix discolor (aka: Pussy willow, American pussy willow, Glaucous willow, Large pussy willow)
Salix nigra (aka: Black willow, Swamp willow, Southwestern black willow, Gulf black willow, Scythe-leaved willow)
Pyrus communis (aka: European pear, Common pear)
Acer negundo (aka: Boxelder, Western boxelder, Arizona boxelder, California boxelder, Texas boxelder, Interior boxelder, Violet boxelder)
Populus tremuloides (aka: Quaking aspen, Trembling aspen, Aspen, American aspen, Mountain aspen, Golden aspen, Trembling poplar, White poplar, Popple, Alamo Blanco)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Vaccinium angustifolium (aka: Lowbush blueberry, Early low-bush blueberry, Low sweet blueberry)
Prunus cerasus (aka: Sour cherry, Tart cherry, Dwarf cherry, Montmorency cherry)
Prunus pumila (aka: Sandcherry, Western sandcherry, Eastern sandcherry, Great Lakes sandcherry)
Liriodendron tulipifera (aka: Tuliptree, Blue-poplar, Tulip-poplar, Yellow-poplar, Yellow wood)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Ulmus americana (aka: American elm, White elm, Water elm, Soft elm, Florida elm)
Prunus americana (aka: American plum, Goose plum, River plum, Wild plum)
Malus domestica (aka: Pyrus pumila, Malus pumila, Apple)
Acer platanoides (aka: Norway maple)
Acer saccharum (aka: Sugar maple, Rock maple, Hard maple)