Jointed charlock

Raphanus raphanistrum

Raphanus raphanistrum is a flowering plant in the family Brassicaceae. It is sometimes claimed to be the ancestor of the edible radish, "Raphanus sativus". Native to Asia, it has been introduced into most parts of the world, and is regarded as a damagingly invasive species in many areas.
Jointed Charlock (Raphanus raphanistrum) INTRODUCED. Growing in an overgrown backyard habitat. Geotagged,Jointed charlock,Raphanus raphanistrum,Spring,United States

Appearance

Wild radish grows as an annual or biennial plant, with attractive four-petalled flowers 30-40 mm across and varying in colour, usually from white to purple but sometimes light orange to yellow, often with colour shading within a single petal. It is frost hardy, and even hard freezes only temporarily interrupt bloom. It blooms in early spring to late summer with flowers very similar to those of the searocket, which is found in some of the same regions and is easily distinguished from it by having thinner, non-succulent stems and leaves. It has a single taproot which is similar to that of the cultivated radish but less enlarged.
Raphanus raphanistrum subsp. rostratus  Jointed charlock,Raphanus raphanistrum

Distribution

In southeastern USA, the pale yellow form is common, sometimes entirely taking over fields in wintertime. It is often erroneously identified as mustard. It is a significant source of pollen and nectar for a variety of pollinators, especially honey bees during the very early spring starting buildup. Female "Andrena agilissima", mining bees"," frequent this plant to obtain pollen and nectar.

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