Sisymbrium
(an old Greek name, used by Theophrastus for Mint). Hedge Mustard. Including Alliaria. ORD. Cruciferae. A genus comprising eighty species of hardy, mostly annual or biennial herbs, usually inhabiting the temperate and cold regions of the Northern hemisphere, but rarely occurring in the Southern. Flowers usually yellow, rarely white or rose, loosely racemose, rarely axillary. Radical leaves stellate; cauline ones alternate. Five species are included in the British Flora: S. Alliaria (Garlic Mustard, Jack-by-the-Hedge, Sauce Alone), S. Irio (London Rocket, so called because it sprang up after the Great Fire), S. officinale (Bank Cress, common Hedge Mustard), S. Sophia (Flixweed), and S. Thaliana (Thale Cress). The genus has no horticultural value.