Seed and leaf alkaloids of Lupinus argenteus were examined at seven different sites in western Colorado by capillary GLC and GLC-MS. As compared to other lupin species variation of alkaloid patterns between and within sites is substantial. At least five different alkaloid profiles were observed. A preliminary garden experiment where seeds from two different locations were grown under identical conditions produced the same alkaloid pattern as found in the plants grown in the wild. This indicates that the chemotype differences are probably genetically based and not caused by differing environmental conditions or a sampling artefact. © 1994.