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.
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)
Calendula officinalis (aka: Marigold, Calendula, Pot marigold, English marigold)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Citrullus lanatus (aka: Watermelon)
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)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)