Symphyotrichum lanceolatum is a perennial herb 20 cm to 2 m tall; roots probably associated with VA mycorrhizas (Chmielewski and Semple 2001a), colonial from long rhizomes, stems smooth or inconspicuously hairy in lines near top; new stems arising from buds or rosettes of scale leaves on rhizomes, 5-15 cm from previous years stems.
Leaves alternate, stalkless, no basal leaves, blades of main stem leaves 8-15 cm long, 0.2-3.5 cm wide, lance-shaped to narrowly elliptic, dark green above, midrib pale, paler green below, usually smooth, lustrous to slightly rough above, secondary veins not impressed, margin usually slightly toothed, tapering to narrow base, often slightly clasping, lower leaves often deciduous, but in general plant remaining very leafy when flowering, upper leaves small, about 1 cm long, often linear.
Flowers: Ray flowers 16-47 white to pale blue 0.5-1.2 cm long, about 0.1 cm wide, disk flowers yellow, 20-40, becoming purplish with age, often fragrant, containing nectar; bracteate base of flower heads 0.3-0.6 cm, bracts flat, in several rows, tip green, pointed; inflorescence branches developing in upper axils during late summer flower heads rather numerous, but scattered, or clustered at branch tips, not dense; Sept.-Oct. probably pollinated by bumblebees, bees, flies, moths and wasps, but possibly self fertile within a colony when outcrossing has not taken place (Chmielewski and Semple 2001).
Fruit dry, 1-seeded (achene), appressed hairy, with a single whorl of bristles (pappus) to 0.6 cm long (longer than disk flowers); relatively few fruits produced per flower; seeds wind dispersed during winter, eaten by birds and small mammals, leaves eaten by rabbits and deer (Martin et al. 1951).
Wetland status: FACW.
Frequency in NYC: Common.
Habitat: Moist to wet soil in sun or part shade of woodlands, edges, roadsides, moist second growth woods, disturbed habitats, open swamp forests. Found on soils pH 4.6-7.8 (Gargiullo unpublished data).
Notes: A successional plant, found in old fields 2-8 years old, tending to colonize sites earlier than Solidago canadensis however, panicled aster has a looser rhizome mat with fewer connections between stems than does Canada goldenrod and over time the goldenrod invades and displaces colonies of the aster where they co-occur. Newly unfolded leaves have the highest rate of photosynthesis, chlorophyll and nitrogen content but calcium content increases with leaf age; various chemicals including the flavonoids quercetin and kampferol have been extracted from lined aster, these compounds act as feeding stimulants for certain beetles (Harborne 1988; Chmielewski and Semple 2001). Flowers parasitized by the gall midge Rhopalomyia asteriflorae (Cercidomyiidae, Diptera), midges of this genus specialize on plants in the family Asteraceae. Leaves infected by the fungus Sclerotium asteris (Deuteromycotina) are then often attacked by the gall midge Asteromyia paniculata (Cercidomyiidae), the fungus, in turn, derives nutrients from the midge feces (frass) and helps shelter the midge larva in a black structure, midges produce several generation per season and attack leaves progressively higher on the stem as it grows during the summer, galls are 0.4-1 cm wide, blister-like, of variable color depending on host species (Agrios 1988; Gagné 1989). Aster lanceolatus is also preyed on by various leaf miners, including the flies Agromyza sp., Phytomyza albiceps (Diptera); a beetle, Sumitrosis inaequalis (Coleoptera, Chrysomelidae); and case bearing moths, Coleophora sp., Coleophoridae) (Johnson and Lyon 1991; Covell 1984; Downie and Arnett 1996). May be infected by the rust fungi Coleosporum asterum and Puccinia dioicae var. asteris (Basidiomycotina); and a powdery mildew, Erysiphe cichoracearum (Ascomycotina), (Agrios 1988; Chmielewski and Semple 2001). Used as a medicinal by Native Americans (Chmielewski and Semple 2001).