Taxonomy

Symphyotrichum novi-belgii (L.) G.L.Nesom, Phytologia 77: 287. 1995.

Common synonyms

Aster novi-belgii L. Sp. Pl. 2: 877. 1753.

Common name

New York aster, Michelmas daisy

Description

Propagule or dispersal unit is the fruit with pappus. Fertile part 1.8-2.6 mm long, 0.3-0.8 mm wide, in side view widest in upper part (obovoid) or widest in the middle, +/- straight, the upper (apical) end narrowing, in cross-section flattened or angular (prismatic), basal scar (carpopodium) pronounced and well-differentiated, central, beak (=thinner sterile stalk between seed and pappus) absent, wings absent, fruit surface light brown or straw, smooth (except at cellular level), with no hairs (glabrous) or simple straight hairs, thickened margin absent, longitudinal ribs present, 3-5, their surfaces smooth, with no hairs (glabrous) or simple straight hairs.

Pappus type bristles / hairs, pappus elements all +/- similar, up to 4-6 mm long, in one row, pappus elements numerous, persistent, rarely elements falling off individually, the individual bristles rough / serrated (barbellate), +/- equal width along length, white / translucent.

Notes: Unfortunately, the Symphyotrichum species cannot be differentiated in this fruit key.