138.
Erigeron glabellus
Nuttall, Gen. N. Amer. Pl. 2: 147. 1818.
Streamside fleabane
Biennials or perennials,
7—50(—70) cm; rhizomatous, caudices or rhizomes relatively short and thickened, simple or branched, usually appearing merely fibrous-rooted.
Stems
erect or slightly basally ascending, hirsute or hirsuto-villous to strigose or glabrate, eglandular.
Leaves
basal (persistent) and cauline; basal blades oblanceolate to oblanceolate-spatulate, 40—150 × 3—15 mm, margins usually entire, sometimes shallowly dentate, faces hirsute or hirsuto-villous to sparsely strigose or glabrate, eglandular; cauline blades usually becoming lanceolate, abruptly or gradually reduced distally (bases sometimes subclasping).
Heads
1—15.
Involucres
5—9 × 10—20 mm.
Phyllaries
in (2—)3—4 series (greenish) , hirsute to strigose, eglandular.
Ray florets
125—175; corollas white to pink or blue, 8—15 mm, laminae (nearly filiform) coiling tardily at tips.
Disc corollas
4—5.5 mm.
Cypselae
1.2—1.5 mm, 2-nerved, faces sparsely strigose;
pappi:
outer of setae, inner of 16—20 bristles.
Varieties 2 (2 in the flora): North America.
Erigeron glabellus
is recognized by its subsimple caudices and fibrous-rooted bases, relatively numerous rays with nearly filiform laminae, and nonglandular vestiture.
