Sedges are often overlooked or thought of as clumps of grass. But like everything in nature it seems the more you look, and the closer you look, the more beauty you find. Sedges are distinguished from rushes and grasses by their triangular, solid stems. Hence the saying "Sedges have edges. Rushes are round. Grasses are hollow. What have you found?" This is a great rhyme to remember their differences.
Sedge refers to the 5500 species in the family Cyperaceae including spike-rushes, beak-rushes, cotton-grasses, bulrushes and the many plants in the genus Carex called sedges. The genus Carex contains 2,000 species, 500 native to North America, 248 in Ontario and an amazing 122 species in the County of Simcoe.
Sedge stems are solid with 3 sides. The leaves lie along the stem in 3 verticle planes and are typically closed. They are wind-pollinated plants, attracting insects and providing cover and food for waterfowl. Sedges are durable, yet many are delicate looking. They are often found growing near wetlands but can tolerate drier conditions. Colours range from silvers, brownish bronze, soft blues, gold, reds and everything in between.
And now for our unusual find! To date Bob Bowles has discovered 6 species at the Nature Centre; Drooping woodland sedge (Carex arctata), Graceful Sedge (Carex gracillima), Limestone meadow sedge (Carex granularis) Long-stalked sedge (Carex pedunculata), Woolly sedge (Carex petilta), and our unusual find, Crawe's Sedge (Carex crawei).
Due to its specialized habitat, Crawe's Sedge is seldom encountered. It prefers full sun, wet to moist conditions and very sandy or rocky soil, flat ground mixed with limestone outcrops. It can be found on Alvars, old gravel pits, wet meadows and fens.
It is a rhizomatous perennial that flowers in early spring. The stems arise from the rhizomes and are 2-40 cm tall. The leaves are narrow, 1.8-4.4 mm across and are bundled at the base of the plant. There are 3-5 narrow cylindrical flower clusters (spikes) near the apex of the stem.
Its beauty is missed by many. The best time to see this species is from late May through to early July.
Bob Bowles is teaching a spring and a summer sedge workshop this year at Lakehead University with the Ontario Master Naturalist Program. Bob will also be teaching sedge workshops here at the Robert L. Bowles Nature Centre.