According to observations of naturalists and beekeepers.
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Sinapis arvensis, the charlock mustard, field mustard, wild mustard, or charlock, is an annual or winter annual plant of the genus Sinapis in the family Brassicaceae.
Sinapis arvensis is an aggressive weed that is native throughout most of the temperate regions of Europe, Asia minor, southwest Asia, and North Africa. It has become naturalized throughout much of North America and is a highly invasive species.
This plant is present in at least 62 states/provinces in this country.
Sinapis arvensis reaches on average 20–80 centimeters of height, but under optimal conditions can exceed one meter. The stems are erect, branched, and striated, with coarse spreading hairs especially near the base. The leaves are petiolate (stalked) with a length of 1–4 centimeters. The basal leaves are oblong, oval, lanceolate, lyrate, pinnatifid to dentate, 4–18 centimeters long, 2–5 centimeters wide. The cauline leaves are much reduced and are short petiolate to sessile but not auriculate-clasping.
The inflorescence is a raceme made up of yellow flowers having four petals. The fruit is a silique 3–5 cm long with a beak 1–2 cm long that is flattened-quadrangular.
It blooms from May to October in North America, or May to August, in the UK. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, flies.
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Vaccinium corymbosum (aka: Highbush blueberry, High-bush blueberry, Northern highbush blueberry, Tall blueberry, Rabbiteye blueberry, Blue huckleberry, Tall huckleberry, Swamp huckleberry, High blueberry, Swamp blueberry)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Allium schoenoprasum (aka: Chives)
Brassica napus (aka: Rapeseed)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
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 planifolia (aka: Diamondleaf willow, Planeleaf willow)
Tilia americana (aka: American basswood, Basswood, Linden)
Amorpha fruticosa (aka: Desert false indigo, False indigo-bush, Bastard indigobush, Indigo Bush)
Asclepias syriaca (aka: Сommon milkweed, Butterfly flower, Silkweed, Silky swallow-wort, Virginia silkweed)
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 laciniatus (aka: Cutleaf blackberry, Evergreen blackberry, Slashed blackberry)
Salsola kali (aka: Russian thistle, Tumbleweed, Prickly saltwort)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)
Citrullus lanatus (aka: Watermelon)
Diervilla lonicera (aka: Northern bush honeysuckle, Bush-honeysuckle, Dwarf bush-honeysuckle, Herbe bleue)
Cephalanthus occidentalis (aka: Common buttonbush, Buttonball, Buttonbush, Button willow, Riverbush, Honey-bells)
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)
Hyssopus officinalis (aka: Hyssop)
Calluna vulgaris (aka: Heather, Scotch heather, Common heather, Ling, Simply heather)