According to observations of naturalists and beekeepers.
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Bitter cherry occurs from British Columbia and Vancouver Island south to southern California and east to Montana, Wyoming, Utah, and New Mexico.
This plant is present in at least 11 states/provinces in this country.
Bitter cherry is a native, deciduous, small tree or shrub with spreading to ascending branches. It often forms dense thickets. It generally persists as a medium to tall shrub, 3.3 to 20 feet (1-6 m) in height. With abundant moisture and deep fertile soil, bitter cherry may reach tree height: up to 50 feet (15 m) in some areas.
The leaves are 0.8 to 2 inches (2-5 cm) long and 0.4 to 1.4 inches (1-3.5 cm) wide. The drupelike, ovoid fruit is 0.24 to 0.56 inches (6-14 mm) in diameter and is one-seeded. Roots may spread up to 50 feet (15 m) from the parent plant, sending up adventitious shoots along their length. Bitter cherry has no taproot.
Bloom Period: April-June. Cherries ripen July to September, dispersal occurs August through September.
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Rubus idaeus (aka: Raspberry, Black-haired red raspberry, Brilliant red raspberry, American red raspberry, Red raspberry, Smoothleaf red raspberry, Wild raspberry, Wild red raspberry, Grayleaf raspberry)
Salix monticola (aka: Park willow, Cherry willow, Mountain willow, Serviceberry willow, White willow)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Brassica napus (aka: Rapeseed)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Asclepias tuberosa (aka: Butterflyweed, Butterfly Milkweed, Orange Milkweed, Pleurisy Root, Chigger Flower, Canada root, Fluxroot, Indian paintbrush, Indian posy, Orange root, Orange Swallow-wort, Tuber root, Yellow milkweed, White-root, Windroot, Butterfly love)
Salix geyeriana (aka: Geyer willow, Silver willow)
Salix brachycarpa (aka: Shortfruit willow, Barren-ground willow, Small-fruit sand dune willow, Small-fruit willow)
Rubus parviflorus (aka: Thimbleberry, Western thimbleberry)
Amorpha fruticosa (aka: Desert false indigo, False indigo-bush, Bastard indigobush, Indigo Bush)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Echium vulgare (aka: Viper's bugloss, Blueweed, Blue thistle)
Rubus armeniacus (aka: Himalayan blackberry, Rubus discolor, Rubus procerus)
Salix planifolia (aka: Diamondleaf willow, Planeleaf willow)
Cirsium arvense (aka: Creeping Thistle, Canada thistle, Field thistle, California thistle, Lettuce from hell thistle, Corn thistle, Cursed thistle, Green thistle, Hard thistle, Perennial thistle, Prickly thistle, Small-flowered thistle, Way thistle, Stinger-needles)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Citrullus lanatus (aka: Watermelon)