Carex

Carex is a genus of plants in the sedge family, Cyperaceae, commonly known as sedges. It comprises more than 2,000 species, making it one of the largest genera of flowering plants. Carex species are widespread in temperate and boreal regions and inhabit wetlands, meadows, riverbanks, forests, and alpine habitats. They are mostly perennial herbs with creeping rhizomes or short tufts. Leaves are typically rigid, grasslike, and arranged in three ranks; stems are usually triangular in cross-section.

A distinctive feature of Carex is the fruiting structure: each flower is enclosed by a perigynium, a cup-shaped covering around the ovary, which differentiates Carex from many other Cyperaceae genera. Flowers are usually wind-pollinated and arranged in dense inflorescences of spikelets.

Ecology and habitat: Carex species stabilize soil, filter water, and provide habitat for a range of invertebrates and small vertebrates. They are common in wetlands, fens, marshes, stream banks, and damp woodland floors, as well as tundra and alpine environments.

Taxonomy and diversity: The genus is taxonomically complex, subdivided into several subgenera; species identification often relies on features of the perigynium, spike arrangement, and leaf morphology. There is substantial variation in growth form and habitat among species.

Uses: In horticulture, many Carex species are valued as ornamental grasses and ground covers in moist or shaded areas. They are also used in ecological restoration and erosion control projects.

Conservation: Habitat loss, drainage, and peat extraction threaten some species. Conservation efforts focus on habitat protection and restoration.