Symphyotrichum laeve (Smooth Aster) - photos and description







Upper stem leaves are clasping and have auricles (ear-shaped lobes at base of the leaf blade)

Lower stem leaf in above photo

General: Stout-stemmed plants with green or glaucous foliage, and a decumbent to erect growth habit. Plants glabrous.

Flowers: Inflorescence paniculate with several to many flower heads. Rays are violet in colour, we measured a flower head to 30 mm in diameter. Bracts imbricate with green tips. Involucre measured 5 mm tall.

Leaves: Leaves alternate. Upper stem leaves clasping and auriculate, an upper stem leaf was measured 7.5 cm long by 15 mm wide. Lower stem leaves toothed, have winged petioles, and the base of the blade tapers gradually. A lower stem leaf was measured at 17.5 cm long (including petiole) by 28 mm wide.

Height: Height listed in Budd's Flora to 100 cm, we measured plants to 90 cm tall.

Habitat: Moist ground on prairie, open wooded areas, coulees, and shrubby terrain.

Abundance: Common.

Origin: Native.

Synonym: Listed in some of the field guides we use as Aster laevis.

Similar species: This plant is very similar to Symphyotrichum ciliolatum. To distinguish between the two:

- The basal leaves and lower stem leaves of Symphyotrichum ciliolatum are both cordate and stalked, ligules blue (Taxonomic Reminder for Recognizing Saskatchewan Plants). The leaves of S. laeve are not cordate.

- Symphiotrichum laeve has some stem leaves auriculate-clasping, is glabrous and glaucous, ligules blue (Taxonomic Reminder for Recognizing Saskatchewan Plants). The leaves of S. ciliolatum are not auriculate.

- I have observed S. ciliolatum grows under tree cover, while S. laeve can be found along roadsides, in ditches, and edges of trees, not usually under tree cover.

When and where photographed: Photos taken July 30th, and 31st on forest roadsides, boreal forest, about 400 km northeast of Regina, SK, and August 20th on a forest roadside Duck Mountain Prov Park, about 300 km northeast of Regina, SK, and September 2nd in a roadside ditch about 70 km north of our home in Regina, SK.