HORSEWEED, Conyza canadensis (L.) Cronq. 1, lower part of leafy stem; 2, upper part of stem with flowers; 3, mature flower head; 4, seed; 5, distribution. Annual, reproducing by seed. Stem stout, erect, unbranched at base, 1 to 6 feet (0.3 to 1.8 m) tall, with bristly hairs. Leaves numerous, without petioles, linear, dark green, with scattered coarse white bristles, margins toothed or entire. Flower heads numerous, small, in axillary panicles, a narrow-pointed bract at the base of each head. Ray flowers greenish-white, scarcely noticeable, surrounding yellow disk flowers. Seeds about 1/16 inch (1.5 mm) long with numerous slender white bristles on one end. Found in pastures, roadsides, and wasteland. Also known as marestail.

 DWARF FLEABANE, Conyza ramosissima Cronq. 6, plant; 7, distribution. Similar to the above but smaller and bushy. Stem 6 to 18 inches (15 to 45 cm) tall, much branched. Leaves narrow. Flower heads few, scattered. Found in dry fields and old pastures.