About Symphyotrichum firmum (Nees) G.L.Nesom
Symphyotrichum firmum is a perennial herbaceous plant that can grow up to 2 meters (6+1⁄2 feet) tall. It forms large colonies via long, creeping rhizomes. Its stem is either hairless, or covered in short, stiff hairs that often grow in vertical lines; the stem nodes (points where leaves connect to the stem) are sometimes dark red or purple. Leaves are arranged alternately, grow up to 15 centimeters (6 inches) long and 3 centimeters (1+1⁄5 inches) wide, and clasp the stem. The main vein on the lower leaf surface is hairless, or slightly hairy near the leaf tip. This species flowers from August through October. Its flower heads measure 1.5 to 3.5 centimeters (5⁄8 to 1+3⁄8 inches) across, with up to 40 ray florets and 50 disc florets. Ray florets can be white, pale blue, or lavender. Disc florets start yellow to cream-colored, and turn pink or purple as they mature. S. firmum is diploid, with a base chromosome number of x = 8 and total chromosome count 2n = 16. When compared to its close relative Symphyotrichum puniceum, S. firmum has less overall hair, denser clusters of smaller, whiter flowers, and grows in larger, denser patches. Due to confusion with the closely related S. puniceum, the full range of S. firmum is not well known. In Canada, it has been recorded from Alberta to Quebec. In the United States, it grows in the Midwest, parts of the Northeast, and the Appalachian Mountains as far south as Georgia. It is more common in the western portion of its range. S. firmum grows in moist, sunny areas such as fens and wet prairies, and is often found growing alongside S. puniceum. Unlike S. puniceum, S. firmum can sometimes spread into drier areas. Observed bee species that visit the flowers of S. firmum include the bicolored striped-sweat bee (Agapostemon virescens), various bumble bees (Bombus species), small carpenter bees (Ceratina species), the sweat bee Halictus ligatus, and Drury's long-horned bee (Melissodes druriellus).
