According to observations of naturalists and beekeepers.
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Brassica napus (Oleifera Group) is commonly called rapeseed. It is the third-largest source of vegetable oil in the world (behind palm oil and soybean oil). It is primarily grown as a commercial crop for the production of vegetable oil (rapeseed oil) from its seeds, for production of biodiesel from rapeseed oil, for its young edible leaves or as forage for livestock.
Rapeseed is also used as a cover crop in the US during the winter as it prevents soil erosion, produces large amounts of biomass, suppresses weeds, and can improve soil tilth with its root system. Some cultivars of rapeseed are also used as annual forage and are ready for grazing livestock 80 to 90 days after planting.
This plant is present in at least 51 states/provinces in this country.
Brassica napus grow to 100 cm in height with hairless, fleshy, pinnatifid, and glaucous lower leaves which are stalked whereas the upper leaves have no petioles. Brassica napus can be distinguished from Brassica nigra by the upper leaves which do not clasp the stem, and from Brassica rapa by its smaller petals which are less than 13 mm across.
Rapeseed flowers are yellow and about 17 mm across. They are radial and consist of four petals in a typical cross-form, alternating with four sepals. They have indeterminate racemose flowering starting at the lowest bud and growing upward in the following days. The flowers have two lateral stamens with short filaments, and four median stamens with longer filaments whose anthers split away from the flower's center upon flowering.
It is in flower from May to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. The plant is self-fertile.
Cercis orbiculata (aka: California redbud, Western redbud, Arizona redbud, Judas tree, Cercis occidentalis)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Salix lutea (aka: Yellow willow)
Salix scouleriana (aka: Scouler's willow, Upland willow)
Prunus emarginata (aka: Bitter cherry)
Prunus andersonii (aka: Desert peach, Desert peachbush, Anderson peachbush, Wild almond)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
Salix boothii (aka: Booth's willow)
Salix lemmonii (aka: Lemmon's willow, Lemmon willow)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
Salix amygdaloides (aka: Peachleaf willow, Peach leaf 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)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Brassica napus (aka: Rapeseed)
Allium schoenoprasum (aka: Chives)
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 virginiana (aka: Chokecherry, Western chokecherry, Common chokecherry, Black chokecherry)
Rubus parviflorus (aka: Thimbleberry, Western thimbleberry)
Salix geyeriana (aka: Geyer willow, Silver willow)
Salix planifolia (aka: Diamondleaf willow, Planeleaf willow)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Rubus armeniacus (aka: Himalayan blackberry, Rubus discolor, Rubus procerus)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Citrullus lanatus (aka: Watermelon)
