Solidago canadensis L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Perennial, mostly with long, creeping rhizomes (rhizome short in var. gilvocanescens), 2.5–20 dm, the stem ± puberulent at least above the middle; lvs chiefly cauline, numerous, triple-nerved, lance-linear to lance-elliptic or narrowly elliptic, sessile, tapering to both ends, the larger ones 3–15 cm × 5–22 mm, puberulent at least on the midrib and main veins beneath; infl mostly paniculiform, with strongly recurved-secund branches (varying to thyrsoid and not secund in var. salebrosa); invol 2–4(–5) mm, its bracts imbricate, thin and slender, acute or acuminate, yellowish, without a well defined green tip; rays 10–17 (or fewer in var. hargeri), 1–3 mm; disk-fls 2–8 (to 13 in var. salebrosa); achenes short-hairy; 2n=18, 36, 54. Moist or dry open places and thin woods; throughout most of the U.S. and s. Can.