Cirsium scopulorum, or mountain thistle, was long thought to be the only species of thistle occurring in the alpine tundra. Molecular, morphological, and geographical evidence now support the recognition of many species of thistles in the alpine tundra of the southern Rocky Mountains. We talk with Jennifer Ackerfield, the head curator of natural history collections, and the associate director of biodiversity research at Denver Botanic Gardens about her quest to delineate the many varieties of thistles across the alpine of the intermountain west, including a unique species right here in the La Sal Mountains of SE Utah.