forms upright clusters of many light purple flowerheads borne on branched, reddish stalks. Leaves are plentiful, both around the base and along the stems, where they are only slightly reduced in size. Flowerheads consist of between 16 and 60 ray florets and 50 to 150 yellow disc florets.
The involucral bracts (phyllaries), underneath the flowers, provide one means to distinguish the leafy aster from other similar species such as symphyotrichum ascendens
; they are light green to reddish green in color (whitish at the base), leaf-like in appearance, hairy (usually), and the lowest few are noticeably longer, projecting outwards to nearly the same extent as the petals.
This species is very variable in characteristics, reflecting the wide range of environments it inhabits; four varieties are recognized (apricom, parryi, canbyi, foliaceum), differentiated by the number of flowerheads, the stem height, and the length, color and shape of the phyllaries.