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.
Rubus ursinus (aka: California blackberry, California dewberry, California grapeleaf dewberry, Douglasberry, Pacific blackberry)
Rubus laciniatus (aka: Cutleaf blackberry, Evergreen blackberry, Slashed blackberry)
Salix lutea (aka: Yellow willow)
Salix geyeriana (aka: Geyer willow, Silver willow)
Allium schoenoprasum (aka: Chives)
Brassica napus (aka: Rapeseed)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed 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)
Salix brachycarpa (aka: Shortfruit willow, Barren-ground willow, Small-fruit sand dune willow, Small-fruit willow)
Rubus parviflorus (aka: Thimbleberry, Western thimbleberry)
Rubus armeniacus (aka: Himalayan blackberry, Rubus discolor, Rubus procerus)
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)
Echium vulgare (aka: Viper's bugloss, Blueweed, Blue thistle)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Asclepias syriaca (aka: Сommon milkweed, Butterfly flower, Silkweed, Silky swallow-wort, Virginia silkweed)
Agastache foeniculum (aka: Giant hyssop, Blue giant hyssop, Anise hyssop, Fragrant giant hyssop, Lavender giant hyssop)
Chamaenerion angustifolium (aka: Fireweed, Great willowherb, Rosebay willowherb, Saint Anthony's Laurel, French-willow)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Hyssopus officinalis (aka: Hyssop)
