21. Solidago rugosa Mill. (rough-leaved goldenrod, rough-stemmed goldenrod)
Pl. 240 a, b;
Map 1010
Plants with
branched, long-creeping rhizomes, often also thickened at the stem bases. Stems
1 to few, 30–150(–200) cm long, erect to loosely ascending, with several fine,
longitudinal ridges or grooves, moderately to densely pubescent with short,
mostly spreading hairs 0.1–1.2 mm long (sometimes less densely hairy toward the
stem base), not shiny, not glaucous. Leaves chiefly cauline, the largest leaves
about 1/3 of the way up the stem, the basal and lower stem leaves withered or
absent at flowering (additional rosettes usually absent). Basal and lowermost
stem leaves with the blade 6–12 cm long, 1–3 cm wide, mostly 3–8 times as long
as wide, elliptic to lanceolate, sometimes relatively thick and stiff, angled
to a sessile or occasionally very short-petiolate base, angled or tapered to a
sharply pointed tip, the margins sharply toothed and inconspicuously hairy, the
upper surface glabrous or sparsely to moderately roughened with short, stiff,
broad-based hairs (sometimes only along the midvein) or occasionally with
somewhat softer pubescence, the undersurface moderately to densely pubescent
with spreading or curved hairs, with 1 main vein, the pinnate secondary veins
sometimes strongly raised, easily observed (usually forming an irregular
network). Median and upper stem leaves 1–12 cm long, ovate to elliptic or
lanceolate, the margins toothed or those of the uppermost leaves entire,
otherwise similar to the lower stem leaves. Inflorescences narrow to broad,
open, more or less pyramidal panicles, the branches usually arched or nodding,
the lowermost branches sometimes relatively long, the heads oriented upward
along the branches. Involucre 2.5–4.5 mm long, the bracts in 3 or 4 unequal
series. Involucral bracts lanceolate to narrowly oblong-lanceolate and bluntly
to sharply pointed at the appressed-ascending tip, the thin, white to yellowish
white margins hairy (at least toward the tip), the outer surface glabrous, with
an elliptic or narrowly diamond-shaped, green to light green central region
mostly above the midpoint, this tapered gradually to the midvein, the midvein
often slightly thickened and keeled and no additional veins present. Receptacle
naked. Ray florets 6–11, the corollas 1.5–3.0 mm long, yellow. Disc florets 3–8,
the corollas 2–4 mm long, the lobes 0.7–1.2 mm long, yellow. Pappus 2.0–2.5 mm
long, a few of the bristles often slightly thickened toward the tip. Fruits 0.9–1.5
mm long, narrowly obovoid, finely hairy. 2n=18, 36, 54. August–October.
Scattered mostly
in the southeastern quarter of the state (eastern U.S.
west to Wisconsin and Texas;
Canada).
Bottomland forests, banks of streams, rivers, and spring branches, fens, bases
and ledges of bluffs, and less commonly mesic to dry upland forests; also
pastures and roadsides.
Infraspecific
variation in this is complex and poorly understood, and a number of subspecies
and varieties have been named. There has not been any attempt to correlate the
morphological features with the three ploidy levels recorded thus far. For
further discussion see the treatments of the accepted varieties below.