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.
Prunus pumila (aka: Sandcherry, Western sandcherry, Eastern sandcherry, Great Lakes sandcherry)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Salix lutea (aka: Yellow willow)
Malus ioensis (aka: Bechel crab, Crab apple, Iowa crab, Iowa crab apple, Prairie crab, Prairie crab apple)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
Catalpa speciosa (aka: Northern catalpa, Hardy catalpa, Western catalpa, Cigar tree, Catawba-tree, Bois chavanon)
Rhamnus cathartica (aka: Common buckthorn, European buckthorn, Dahurian buckthorn)
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)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Gleditsia triacanthos (aka: Honey locust, Honey shucks locust, Common honeylocust, Sweet bean locust)
Prunus serotina (aka: Black cherry, Wild black cherry, Rum cherry, Mountain black cherry, Wild cherry)
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)
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)
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)
Echium vulgare (aka: Viper's bugloss, Blueweed, Blue thistle)
Agastache foeniculum (aka: Giant hyssop, Blue giant hyssop, Anise hyssop, Fragrant giant hyssop, Lavender giant hyssop)
Prunus virginiana (aka: Chokecherry, Western chokecherry, Common chokecherry, Black chokecherry)
