Digitalis purpurea range of colours from white through pink to purple, such as "Dalmatian Purple". Cultivated forms often show flowers completely surrounding the central spike, in contrast to the wild form, where the flowers only appear on one side. "D. purpurea" is easily grown from seed or purchased as potted plants in the spring. The following selections have gained the Royal Horticultural Society's Award of Garden Merit: "Digitalis purpurea" is hardy to zones 4-9. Digoxigenin (DIG) is a steroid found exclusively in the flowers and leaves of the plants "Digitalis purpurea" and "Digitalis lanata". It is used as a molecular probe to
Radioactive contamination from the Rocky Flats Plant tests." As noted by Carl Johnson in Ambio, "Exposures of a large population in the Denver area to plutonium and other radionuclides in the exhaust plumes from the plant date back to 1953." Weapons production at the plant was halted after a combined FBI and EPA raid in 1989 and years of protests. The plant has since been shut down, with its buildings demolished and completely removed from the site. The Rocky Flats Plant was declared a Superfund site in 1989 and began its transformation to a cleanup site in February 1992. Removal of the plant and surface contamination was