45. Carex sparganioides Muhlenberg ex Willdenow, Sp. Pl. 4(1): 237. 1805.
Plants without conspicuous rhizomes. Culms 30–100 cm, 3–6 mm wide basally, 0.7–1.1 mm wide distally. Leaves: proximal sheaths loose, longitudinally green-and-white-striped, green-and-white-mottled, with prominent cross veins on backs, fronts hyaline and transversely rugose; ligules 3–8 mm, as long as wide; widest leaf blades 5–10 mm wide. Inflorescences with 6–15 spikes, 3–15 cm × 8–12 mm, occasionally compound and then somewhat larger; proximal internodes usually 20+ mm, more than 2 times as long as proximal spikes; proximal bracts to 2 cm; spikes with up to 50 ascending to spreading perigynia. Pistillate scales hyaline with green midvein, ovate to subcircular, 1.8–2.5 × 1.1–1.8 mm, body 1/2 length of perigynium, apex obtuse to acuminate or short-awned. Anthers 0.7–1.3 mm. Perigynia pale green, with wing 0.1–0.2 mm wide distally, veinless or weakly veined abaxially, 3.3–4.3 × 1.5–2.5 mm, margins serrulate distally; beak 0.8–1.2 mm, apical teeth 0.2–0.4 mm. Achenes suborbiculate, 1.7–2.2 × 1.5–1.8 mm. 2n = 46, 48.
Fruiting late spring–early summer. Dry to moist deciduous and mixed forests, forest edges, on neutral or basic soils; 50–300 m; Ont., Que.; Ark., Conn., Del., D.C., Ga., Ill., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., Ohio, Pa., S.Dak., Tenn., Vt., Va., W.Va., Wis.