About Symphyotrichum pilosum (Willd.) G.L.Nesom
Symphyotrichum pilosum is a perennial herbaceous flowering plant. Most individuals grow between 20 cm (8 in) and 120 cm (4 ft) in height, though some can be as short as 5 cm (2 in) and others reach or exceed 150 cm (5 ft). It flowers from late summer to late fall, with flowering ending in October in northern regions and December in more southern areas. There are two recognized varieties: Symphyotrichum pilosum var. pilosum and Symphyotrichum pilosum var. pringlei. The two varieties differ in morphology, chromosome count, distribution, and habitat. S. pilosum var. pilosum is the autonym, with hairy stems and leaves. It is widespread and often weedy. It tolerates harsh growing conditions, and is most often found at elevations between sea level and 1,000 meters (3,300 feet) in disturbed areas, including fallowed land, old fields, roadsides (including salted roadsides), railroads, pastures, landfills, and quarries. It occurs less frequently in natural prairies, open deciduous woods, and limestone outcrops, and is very uncommon in wetlands. Hexaploid individuals of this variety are usually found in habitats that were once covered by glaciers. S. pilosum var. pringlei is hairless, less common, and often grows in high-quality habitats. It is common in calcium-rich ecosystems such as calcareous grasslands and fens, limestone alvars, shale outcrops, and marly pannes. It has also been found in various partially sandy or sandy areas, on moraine cliffs along lakes in woodland openings, and in similar environments. It can be found in habitats that are typical for S. pilosum var. pilosum almost as often as it is found in the higher-quality habitats noted earlier. Recorded elevations for this variety range from sea level to 1,100 meters (3,600 feet), and sometimes higher. In cultivation, Symphyotrichum pilosum var. pringlei and its cultivar 'Ochtendgloren' have both received the Royal Horticultural Society's Award of Garden Merit.
