Arabis glabra Tower mustard

Arabis glabra
©Simon Williams/Plantlife

A tall, slim, grey-green plant with small creamy flowers at the top of the stem. It usually grows on poor chalky or sandy soils, in open situations.

This plant was never common, but has declined in recent decades and now only 25 sites remain, mostly in Norfolk, (where 100 plants were found at a new site in 1999), and the southern counties of England.

Habitat destruction due to intensive agriculture is its main threat, as well as habitat neglect, which results in smothering by coarse vegetation.

Classified as Endangered, it is considered to be facing a very high risk of extinction in the wild. In addition it is listed as a Priority Species under the UK Biodiversity Action Plan.