bristly sedge

LC - Least Concern

NNR - Unranked

SNR - Unranked

not listed

OBL - Obligate wetland

OBL - Obligate wetland

OBL - Obligate wetland

Bristly sedge is a large, broad-leaved, true sedge. It occurs in the eastern United States from Maine to Florida west to Minnesota and Louisiana, in the west from Washington to California, in adjacent Canadian provinces, and in Mexico. It is found in swamps, marshes, wet thickets, and depressions in wet meadows; on the shores of ponds and lakes; and on floating mats of vegetation. It is often emergent in shallow water, near or even well away from the shore. It sometimes roots on floating logs.

Bristly sedge is an erect, perennial sedge that rises in a loose or dense clump from a short, horizontal, underground stem (rhizome) and fibrous roots.

Both sterile (vegetative) and fertile (flowering) stems (culms) are produced, more of the former than the latter. The vegetative culms are well-developed and have several leaves. Flowering culms are 20″ to 47″ (50 to 120 cm) tall. They are erect, unbranched, leafy, and three-sided with sharp edges. They are hairless, rough to the touch near the top, and tinged brownish at the base.

Stem leaves are alternate and widely spreading to ascending. They appear along the entire length of the culm below the inflorescence. All of the leaves, even at the base, have well-developed blades. The leaf blade is hairless, light green to medium green, 8″ to 20″ (20 to 50 cm) long, and 3⁄16″ to ⅝″ (5 to 16 mm) wide. It is usually W-shaped in cross section, sometimes flat. The sheath is hairless, deeply concave at the tip, light green and veined on the outer side, papery (membranous) on the inner side. The sheath of the lowermost leaves is pale brown at the base. The sheath does not break into horizontal ladder-like fibers as it ages, and there is no red or purple coloration at the base. The sheaths of the previous season persist and are noticeable at the base of the plant. The ligule is V-shaped and longer than wide.

The inflorescence is a 1½″ to 13¾″ (4 to 35 cm) long, loosely spaced arrangement of spikes. There is a single male (staminate) spike at the tip of the stem and 2 to 6 female (pistillate) spikes near the top of the stem. The inflorescence is subtended by a single, 6″ to 33½″ (15 to 85 cm) long, inflorescence leaf (bract). The bract is much longer than the inflorescence.

The staminate spike is cylindrical and 1″ to 3⅛″ (25 to 80 mm) long. It is held erect on a slender stalk (peduncle) that is up to ⅜″ (10 mm) long. Each male flower is subtended by a single modified leaf (scale). The staminate scale is lance-shaped to linear, ⅛″ to ⅜″ (4 to 9 mm) long, and tapered to a rough (scabrous), bristle-like tip (awn). It is reddish-brown and has a green or straw-colored midrib.

The pistillate spikes are cylindrical, ⅝″ to 3″ (15 to 75 mm) long, and ½″ to ¾″ (12 to 18 mm) wide. They are on up to 1″ long or longer peduncles. The upper spikes are spreading, the lower ones drooping. Each spike has numerous fruit capsules (achenes), and each achene has a sac-like covering (perigynium). At the base of each perigynia is a single scale. The pistillate scale is lance-shaped, ⅛″ to ½″ (2.8 to 12 mm) long, 1⁄64″ to 1⁄32″ (0.4 to 1.0 mm) wide, and narrowed with concave sides (acuminate) toward the tip. It is shorter than the perigynium. The tip tapers to a long scabrous awn.

The perigynia are crowded and are spreading to bent backwards (reflexed) when mature. Each perigynium is narrowly egg-shaped. leathery, 3⁄16″ to ⅜″ (4.8 to 8.7 mm) long, and 1⁄32″ to 1⁄16″(1.1 to 1.8 mm) wide. It entirely and tightly envelopes the achene at maturity. It is abruptly contracted into a long beak at the tip. It has 14 to 22 distinct, closely-spaced veins that converge about half way up the beak. The beak is tube-shaped, 1⁄16″to ⅛″ (2 to 4 mm) long, and has two papery teeth at the tip. The teeth are 1⁄32″to ⅛″ (2 to 3 mm) long and are distinctly curved outward.

The achene is dry, pale brown, 1⁄16″ (1.7 to 2.0 mm) long, and triangular in cross section. It matures in late June to mid-September.

20″ to 47″ (50 to 120 cm)

Swamps, marshes, wet thickets, depressions in wet meadows, shores of ponds and lakes, floating mats of vegetation, and floating logs. Often emergent in shallow water.

Late June to mid-September

Sources

2, 3, 4, 5, 7, 24, 28, 29, 30, 84.

Native

Common

Growing on shore of Pine Song Lake

Location: Fairview Twp, Cass County

Growing on shore of Pine Song Lake