Symphyotrichum laeve

Smooth aster is tall. Its leaves are arranged alternately on the stems, and their shape varies among lanceolate, oblong-ovate, oblong-obovate, and ovate. They measure from long and from wide. They are usually hairless, and the leaf edges are entire or bluntly or sharply toothed (crenate or serrate), sometimes with smaller teeth (serrulate). Symphyotrichum laeve 44271027.jpg Symphyotrichum laeve 50344044.jpg The flower heads are arranged in clusters (panicles). Each flower head has 13 to 23 ray florets with pale to dark blue or purple petals (laminae), and 19 to 33 disc florets that start out yellow and eventually turn purplish-red. The whole flowerhead measures across. Symphyotrichum laeve 105736406.jpg Symphyotrichum laeve 145337525.jpg Symphyotrichum laeve 38098561.jpg The seeds are cypselae with pappi (bristles at their tips). Like the hairs on dandelion seeds, the pappi allow the seeds to be spread by the wind. Symphyotrichum laeve 34324805.jpg ==Taxonomy==

There are four varieties: Symphyotrichum laeve var. laeve, S. laeve var. geyeri ('''Geyer's aster'), S. laeve var. concinnum, and S. laeve var. purpuratum''. Hybrids with this species and others of the genus have been reported, including three named as follows: • Symphyotrichum × gravesii between S. laeve var. laeve and S. dumosum; • Symphyotrichum × versicolor between S. laeve var. laeve and S. novi-belgii var. novi-belgii; and, • Symphyotrichum × woldenii between S. laeve var. laeve and S. praealtum, which instead may be between S. oolentangiense and S. praealtum. Aster gravesii (Symphyotrichum x gravesii) specimen (cropped).jpg | Symphyotrichum × gravesii Symphyotrichum x versicolor specimen (cropped).jpg | Symphyotrichum × versicolor Aster woldenii isotype (inflorescence).jpg | Symphyotrichum × woldenii == Distribution and habitat ==

Symphyotrichum laeve varieties are native to Canada, the United States, and Coahuila (Mexico). The species is introduced in Québec and New Brunswick. Symphyotrichum laeve grows in fields, open woods, and along roadsides in rocky or dry soil and full sun. == Ecology ==

Symphyotrichum laeve blooms in late summer and early fall. It is pollinated by many native bees and attracts butterflies. It is a larval host for the pearl crescent butterfly (Phyciodes tharos). ==Conservation==