Monographs Details: Carex x aestivaliformis Mack.
Authority: Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Description:Species Description - Tufted, 4–9 dm, purplish at base; main lvs 2–4 mm wide, the blade glabrous or hairy, the lower (or all) sheaths hairy at least on the back; terminal spike pistillate toward the tip; lateral spikes 2 or 3, usually approximate, ascending or spreading, cylindric, 2–4 cm × 3 mm, long- peduncled; uppermost bracts sheathless or nearly so; pistillate scales ovate-oblong, slightly shorter than the perigynia, acute to acuminate or short-cuspidate; perigynia narrowly ovoid-ellipsoid, 3–3.5 mm, obscurely several-nerved, acuminately tapering to a very short, barely bidentate beak; achene concavely trigonous. Wet woods and meadows; N.H. to Va. and Ga. Rare, perhaps a hybrid of C. aestivalis × gracillima.