Digitalis thapsi than those found in "D. purpurea". According to Dutch botanist Herman Boerhaave, "Digitalis" species are highly poisonous if directly ingested. All parts are poisonous. Besides normal cultivation, "D. thapsi" has been propagated using explant culture, a technique employed for the isolation of cells from piece(s) of tissue for harvesting. Auxins NAA, 2,4-D and IAA alone or combined with BA produced a callus. NAA caused root formation and BA shoot formation. NAA and BA combined induced organ generation much effectively. Plantlets obtained this way had a survival rate of 70%. Joseph Gottlieb Kölreuter, a German botanist, observed that "D. thapsi" had
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