@roots Common names: dyer's greenweed, dyer's broom, dyer's whin, waxen woad, waxen wood Used in yellow dye, and for green when combined with woad - which I learn is still cultivated as a blue dye for (among other things) printer ink! Woad link: https://en.wikipedia.org/wiki/Isatis_tinctoria You have to check out the GBIF link - this dyer's greenweed has SO MANY names in Welsh! (https://www.gbif.org/species/5347612) I count about 9, *plus* several apparently minor variants!