Notes on Brassicaceae
Collins Wild Flower Guide pp. 208-11
Brassica rapa, Turnip: dense inflorescence, buds overtopping open flowers, sepals erect
Brassica napus, Rape: dense inflorescence, flowers overtopping buds
Rhampospermum nigrum, Brasssica nigra, Black Mustard: all leaves stalked
Sinapis alba, White Mustard: all leaves stalked
Rhamphospermum arvense, Sinapis arvensis, Charlock: lower leaves stalked, upper leaves sessile - https://www.naturespot.org.uk/species/charlock
Hirschfeldia incana, Hoary Mustard: stiff white hairs on lower part of stem
Rapistrum rugosum, Bastard Cabbage: stems stiffly hairy, dark green leaves - https://www.naturespot.org.uk/node/253992
Rapanus raphanistrum, Wild Radish: petals may be white, dark veins on petals
https://www.naturespot.org.uk/family/brassicaceae
https://www.naturespot.org.uk/family/brassicaceae?page=1
NB seeds