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DescriptionThis wildflower is a summer annual about ½-2½' tall. A robust plant is unbranched below and abundantly branched above; the stems are light green and hairless (or nearly so). Abundant alternate leaves are located along these stems; they are widely spreading to ascending. Individual leaves are ½-3' and less than 1/8' across; they are simple (non-compound), linear-filiform, sessile, and smooth along their margins. Frequently, these narrow leaves often occur in short axillary clusters (making them appear whorled or palmately lobed); they are light to medium green or grayish blue, glandular-dotted, and hairless (or nearly so). Flowerheads about ¾' across occur individually on erect peduncles about 1-5' long. Each flowerhead has 5-10 ray florets surrounding numerous tiny disk florets (75 or more); both types of florets are yellow. The petal-like rays become wider toward their tips, where they are 3-toothed; their florets are pistillate and fertile. The disk florets have tubular corollas with 5 tiny teeth along their upper rims; they are perfect and fertile. At the base of each flowerhead, there are several linear-lanceolate bracts (phyllaries) that are light green; they extend downward while the flowerhead is blooming. The blooming period occurs from late summer into the fall and lasts 1½-3 months. Both the disk and ray florets are replaced by small achenes (about 1-1.25 mm. in length) that are reddish brown, oblanceoloid, angular, and hairy. Each achene has a crown of several awned scales at its apex. The root system consists of a short branching taproot. This wildflower spreads into new areas by reseeding itself.