Charlock, or Wild Mustard, is a tall annual. The flowers are a bright yellow. The leaves are hairy and coarsely toothed; the lower ones are stalked and large, the upper unstalked and narrow.
Charlock is a tiresome weed of cultivated land and used to be rampant where no selective weedkillers are used, but is now less common. It is supposed to have been used as a food in Famine times.
The flowers bloom in May, June and July.
Charlock grows throughout Europe, south-west Asia and Siberia. It has been introduced in North and South America, South Africa, Australia and New Zealand.