Plant indicators of argillaceous soils

1179. Argillaceous. Common colt's foot (Tussilago Farfara); goose tansy (Potentilla Anserina), silvery (argentea), and creeping (reptans); yellow meadow rue (Thalictrum flavum); Carex, many species; Juncus, various species; tuberous bitter vetch (O'robus tuberosus); greater bird's-foot trefoil (Lotus major), and crow-footed (corniculatus); officinal soapwort (Saponaria officinalis): but the Tussilago Farfara is a certain and universal sign of an argillaceous soil, and is the chief plant found on the alum grounds of Britain, France, and Italy.