Noccaea caerulescens Alpine Penny-cress N
More often found on basic soils in particular limestone this nationally rare plant will also tolerate soils containing usually poisonous heavy metals so in the limestone areas where it is most often found, places like old slag heaps and mine workings are a good place to look. It is quite variable with very short plants and quite tall ones too but no sub species or varieties have yet been defined.
Some time ago the name of this plant changed from Thlaspi alpestre to Thlaspi caerulescens and since 2010 in New Flora of the British Isles, it has been changed again to Noccaea caerulescens.
Noccaea caerulescens has its main strong hold in the Pennines around Teesdale but is found also in small communties in Debyshire, Wales, Somerset and in even smaller numbers in Scotland. It is absent from Ireland.