Single Record

Species: Dieteria bigelovii [Machaeranthera bigelovii] [Machaeranthera aquifolia] [Machaerathera pattersonii] [Aster aquifolia] [Machaeranthera rubricaulis] etc..

Counties: Alamosa, Conejos, Costilla, Hinsdale, Mineral, Rio Grande, Saguache, Archuleta

PhotoRecords: YES Rich Haswell: Mineral Co Beaver Reservoir SW of South Fork Beside parking lot 2 Sept 2020

Comments: Dieteria bigelovii is a very common late summer asterid all around the Watershed, blooming into the fall, often found in lawn, along roads, or in other disturbed ground. Our species is D. bigelovii var. bigelovii (in the past usually treated as Machaeranthera biglovii). Note that where D. bigelovii and D. canescens are sympatric, and that includes the Watershed, they often hybridize. To distinguish the two species, the most reliable key character is width of largest stem leaf: D. bigelovii 5 mm or more, D. canescens 5 mm or less. Another useful trait is presence of stipulate-glandular hairs on the peduncle with D. bigelovii and lack of them with D. canescens. But these distinctions do not always hold. (For a valuable exploration of the differences, see A. Schneider, 2001-current.) D. bigelovii is a Southwestern flower recorded from Arizona, Utah, New Mexico, Colorado, and one county in southeast Wyoming. Although not yet vouchered from the Culebras, it is frequently recorded from their extension into New Mexico, where it follows the Rio Grande drainage down to the Mexican border but no farther.