Broad Leaved Goldenrod

The two cytotypes of Solidago flexicaulis show a strong geographic pattern. Diploids mostly occur east of the Appalachians except in the southwestern portion of the range, while tetraploids occur west of the mountains (J. G. Chmielewski and J. C. Semple 1985). The report of 2n = 90 for the species (Semple et al. 1993) was based on a specimen of the recently described Solidago faucibus. The significance of ploidy level on cypselae traits was analyzed in detail by Chmielewski et al. (1989).

Plants (15–)25–75(–90) cm; caudices woody, rhizomes short. Stems 1–5+, flexuous, sparsely to moderately hairy in arrays. Leaves: rosettes present at flowering; basal and proximal cauline tapering to winged petioles, blades ovate, (70–)100–140(–180) × (27–)40–60(–80) mm (petioles ¹ / 4 – ¹ / 2 total leaf length), margins serrate-serrulate [teeth (14–)21–33(–45)], abaxial faces glabrous or moderately hairy, more densely so on nerves, adaxial glabrous or sparsely hairy; mid to distal cauline sessile, blades narrowly ovate to lanceolate, 38–90(–150) × 10–30(–55) mm, reduced distally, becoming lanceolate in arrays, bases tapering, margins entire to serrate, apices acuminate to cuspidate, faces glabrous or sparsely hairy, abaxial glabrous or moderately hairy, more densely so along nerves. Heads 25–250, in short axillary and terminal racemiform clusters, lateral panicles (2–)7–31(–56) cm. Peduncles 0.5–5 mm, moderately to densely strigose; bracteoles 1–3, lanceolate, usually near base of involucres and grading into phyllaries. Involucres campanulate, 4.5–7(–8) mm. Phyllaries in ca. 3 series, strongly unequal, outermost 1–2 mm, innermost 3.7–4.7(–5.7) mm, linear-oblong, 1-nerved, apices obtuse to acute. Ray florets 1–5; laminae (2–)2.5–4(–5) × 0.7–2 mm. Disc florets 4–8(–11); corollas 2–3(–4) mm, lobes 1–1.6(–2) mm. Cypselae (obconic) 1–2(–3) mm, moderately to densely strigose; pappi 3–4.5 mm. 2n = 18, 36.

Doria flexicaulis (Linnaeus) Lunell; Solidago flexicaulis var. ciliata de Candolle; S. flexicaulis var. latifolia (Linnaeus) Pursh; S. latifolia Linnaeus; S. scrophulariifolia Miller

Solidago flexicaulis, the broadleaved goldenrod, or zigzag goldenrod, is a North American species of herbaceous perennial plants in the family Asteraceae. It is native to the eastern and central parts of the United States and Canada, from Nova Scotia west to Ontario and the Dakotas, and south as far as Alabama and Louisiana. It grows in a variety of habitats including mesic upland forests, well drained floodplain forests, seepage swamp hummocks, and rocky woodlands.

The plant is called the "zigzag goldenrod" because the thin, wiry stem zigs and zags back and forth, changing direction at each node (leaf attachment point). The plant bears sometimes as many as 250 small yellow flower heads, some at the end of the stem, others in the axils of the leaves. The leaves are very broad, almost round, but with an elongated tip at the end and large teeth along the edges.

Solidago flexicaulis shares some similarities to Solidago albopilosa, both molecularly and physically. There is some evidence indicating that the plant is an ancient autopolyploid of S. flexicaulis.

Photo showing elongated inflorescence