The turnip or white turnip (Brassica rapa subsp. rapa) is a root vegetable commonly grown in temperate climates worldwide for its white, fleshy taproot.

The term collard has been used to include many non-heading Brassica oleracea crops. While American collards are best placed in the Viridis crop group, the Acephala cultivar group is also used ("without a head" in Greek) referring to a lack of close-knit core of leaves (a "head") like cabbage does, making collards more tolerant of high humidity levels and less susceptible to fungal diseases.