is a common plant, found in all the western states. The flowers have between 16 and 50 white ray florets and 15 to 45 disc florets, yellow when in bud becoming reddish-brown when mature and elongated. The branched stems are green near the tip but brownish red lower down, woody near the base. Involucral bracts (phyllaries) are narrow, quite long and point generally upwards. There are five varieties, differing in leaf shape, flower distribution, stem hairiness and phyllary characteristics.