Calycadenia truncata is easily the most widespread species in the genus, extending from mountainous southern Oregon south along the Sierran foothills and Coast Ranges and out onto the floor of the Central Valley. Populations can be found at elevations ranging from about 50 to 1500 meters. The flower color is always yellow, sometimes with reddish eyespots on the ray corollas. The peduncular bracts have one terminal tack-shaped gland. The plant surfaces are commonly glaucous and the ray achenes rugose, features found only in C. truncata.
Plants are generally robust with large, showy heads.
Preliminary studies indicate that the species includes three or more chromosome races differentiated by reciprocal translocations. Putative natural interspecific hybrids with C. multiglandulosa have been observed east of Sacramento. Artificial interspecific hybrids have been produced with C. mollis , C. villosa , and Osmadenia tenella .