Life History and Demography of Sclerocactus glaucus and Sclerocactus dawsoniae

Sclerocactus glaucus was listed as threatened under the endangered species act from 1979 until 2021 when it was delisted. Sclerocactus glaucus occurs south of Grand Junction and S. dawsoniae is found in Mesa and Garfield counties northeast of Grand Junction.

A taxonomic split of S. dawsoniae from S. glaucus was recognized at the time of delisting and published in 2024. In 2008 Denver Botanic Gardens scientists began a long-term demographic study of S. glaucus and S. dawsoniae. Monitoring of S. glaucus and S. dawsoniae individuals continued annually to track longevity and reproductive rates, ultimately recording plant height, width, reproductive condition, and herbivory damage on an annual basis.