Field Penny-cress - Thlaspi arvense

Short to medium hairless, erect plant. Stem leaves oblong, clasping the stem closely, lower leaves stalked, not in a rosette. Flowers white 4 to 6 mm anthers yellow. Fruit quite large 10 to 15 mm rounded with a deep notch and broadly winged.

Lepidium 

Rounded fruits with wings all round, notched, with short style not exceeding wing.

Photo of whole plant showing seeds

A weed of waste ground, disturbed and arable land, allotments etc.

May to August.

Annual.

Fairly common throughout Britain.

Fairly frequent in Leicestershire and Rutland but possibly declining. In the 1979 Flora survey of Leicestershire it was found in 102 of the 617 tetrads.

In the current Checklist (Jeeves, 2011) it is listed as Alien (archaeophyte); occasional, but probably rare now on arable land