According to observations of naturalists and beekeepers.
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Field mustard is an upright winter annual or biennial that is a member of the mustard family (Brassicaceae). The oil made from the seed is sometimes also called canola or colza, which is one reason why it is sometimes confused with rapeseed oil.
This species is native to Eurasia, but has spread all over the world and is now naturalized throughout much of North America.
This plant is present in at least 63 states/provinces in this country.
Plants exist as basal rosettes until flowering stems develop at maturity, usually in the second year. Plants grow 1 to 3 (or 4) ft tall from a sometimes fleshy, enlarged taproot, with a many-branched stem. The foliage is generally hairless and sometimes covered with a whitish film. Lower leaves can reach 12 inches long, have a large central lobe, and usually one to four pairs of smaller side lobes. Upper leaves are smaller, non-lobed, and have a pointed tip and widened, clasping base. The bright yellow flowers are clustered at stem tops and have four petals that are 1/4 to 1/2 inch long.
Plants flower from June to August, depending on climate and latitude, and are insect-pollinated and self-incompatible.
Cercis canadensis (aka: Eastern redbud, Redbud, Cersis Reniformis)
Prunus americana (aka: American plum, Goose plum, River plum, Wild plum)
Aronia arbutifolia (aka: Red chokeberry)
Acer saccharum (aka: Sugar maple, Rock maple, Hard maple)
Celtis laevigata (aka: Hackberry, Sugarberry, Lowland hackberry, Sugar hackberry, Arizona sugarberry, Netleaf hackberry, Small's hackberry, Southern hackberry, Texas sugarberry)
Acer negundo (aka: Boxelder, Western boxelder, Arizona boxelder, California boxelder, Texas boxelder, Interior boxelder, Violet boxelder)
Malus domestica (aka: Pyrus pumila, Malus pumila, Apple)
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)
Ilex opaca (aka: American holly, Dune holly, Hummock holly, Scrub holly)
Salix amygdaloides (aka: Peachleaf willow, Peach leaf willow)
Malus ioensis (aka: Bechel crab, Crab apple, Iowa crab, Iowa crab apple, Prairie crab, Prairie crab apple)
Viburnum prunifolium (aka: Blackhaw, Black haw, Blackhaw viburnum, Sweet haw, Stag bush, Smooth Blackhaw Viburnum, Stagbush, Viburnum bushii)
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)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
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)
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)
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)
