Eryngium yuccifolium Michx.

Eryngium yuccifolium Michx. Fl. Bor. Am. 1: 164. 1803
Eryngium aquaticum L. Sp. PI. ed. 2. 336, in part. 1762. Not E. aquaticum L. 1753. Eryngium tuberosum Raf. Fl. Ludov. 60. 1817.
Eryngium aquaticum var. normale H. Wolff in Engler, Pflanzenreich 61 (4 228 ) : 240. 1913. Eryngium aquaticum var. subinerme H. Wolff in Engler, Pflanzenreich 61 (4— s ) : 242. 1913.
Stout, glabrous perennials, 3-18 dm. high, from a fascicle of tuberous woody roots, the stems slender, solitary, branching above; basal leaves rigid, broadly linear, 1.5-10 dm. long, 1-3 cm. broad, acute, remotely bristly with solitary or occasionally 2 or more bristles together, the venation parallel; sheaths short; cauline leaves like the basal, reduced above; inflorescence cymosely branched, the heads large, pedunculate, the flowers numerous; heads globose-ovoid, 1-2.5 cm. in diameter; bracts 6-10, spreading-ascending, ovate-lanceolate, 4-15 mm. long, cuspidate, mostly entire, shorter than the heads; bractlets like the bracts, entire or minutely serrulate, exceeding the fruit; coma wanting; sepals ovate, obtuse, mucronulate; petals oblong, 1.5 mm. long; styles exceeding the sepals; fruit oblong, 4-8 mm. long, the scales of the angles lanceolate, flattened, 1.5-3 mm. long, those of the dorsal surfaces reduced or obsolete.
Type locality: In paludosis Virginiae, Michaux.
Distribution: Connecticut to Florida, west to Minnesota, Kansas, and Texas (Heller 1104,