66. Carex molestiformis Reznicek & P. Rothr.

Map 182

Plants with short, inconspicuous rhizomes, forming tufts or clumps. Vegetative stems shorter than the flowering stems and developing late in the season, the leaves clustered near the tip. Flowering stems 25–120 cm long, much longer than the leaves. Leaves with well-developed blades mostly 3–5 per flowering stem. Leaf blades 2–30 cm long, 1.5–4.0 mm wide, green. Leaf sheaths often extended past the insertion point of the leaf blade, the ventral side white to light yellow, papery, the tip truncate to somewhat concave, the ligule mostly wider than long and U-shaped. Inflorescence straight or somewhat bent immediately above the lowermost spike, the 2–5 spikes densely overlapping along the axis, the lowermost spike sometimes more loosely spaced. Spikes 7–17 mm long, 5–10 mm wide, the pistillate portion circular to broadly ovate or obovate in outline, rounded at both ends, with usually numerous perigynia with appressed to ascending or somewhat spreading tips, the staminate portion usually inconspicuous. Scales 2.5–5.0 mm long, shorter and narrower than, but not hidden by the perigynia, narrowly ovate, rounded to sharply pointed, white to light yellowish brown with a green or pale brown midrib. Perigynia 4.0–5.4 mm long, 2.4–3.2 mm wide, 1.3–1.9 times as long as wide, flat to slightly concave on the ventral side and somewhat convex on the dorsal side, the main body as long as wide or slightly longer than wide, broadly ovate-elliptic, widest at or below the middle, broadly winged to the base, rounded gradually to a beak with toothed or roughened margins, the wing extending to the tip of the beak, the ventral and dorsal surfaces lacking papillae, sharply 4–6-nerved on the ventral surface and finely 6–11-nerved on the dorsal surface, greenish brown to light brown. Fruits 1.6–2.0 mm long, 1.4–1.6 mm wide, 1.0–1.3 times as long as wide, broadly oblong to nearly circular in outline, light brown to brown. 2n=74. May–July.

Uncommon in the eastern half of the Ozark Division (endemic to the Ozarks of Arkansas, Missouri, and Oklahoma). Banks of streams, rivers, and spring branches, bottomland forests, open bottoms of ravines in mesic upland forests, fens, and shaded dolomite bluffs.

This recently described Ozark endemic (Reznicek and Rothrock, 1997) refers to a series of populations that consistently have perigynia at the large end of the range of variation for C. molesta, and which differ from that species in the shape of their fruits. The plants also tend to have stems that are stouter toward the tip. Some specimens of C. molestiformis originally were determined as C. brevior, because the spikes with more ascending perigynia superficially resemble that species. However, C. brevior has the perigynia nerveless or nearly so.