Gahnia radula, commonly known as Thatch Saw-sedge, is a tufted perennial sedge native to the understory of eucalypt forests and grassy woodlands in southeastern Australia, including Tasmania. It typically grows to a height of 20-39 inches (50-100 cm) and spreads through rhizomes. This sedge has long, rough, strap-like leaves with sharp edges that can reach several feet in length. The distinctive brown inflorescences, which darken to black as they mature, appear on tall stems above the foliage and are most notable in summer and autumn.

Thatch Saw-sedge is valued for its textural contrast in gardens and landscapes, particularly in naturalistic plantings and as a ground cover in shaded areas. It is also used for erosion control due to its rhizomatous growth habit. Gahnia radula prefers moist, well-drained soils and can tolerate partial shade to full sun conditions. While it is generally low-maintenance, it may require occasional trimming to remove old foliage and spent flower stems. It is not commonly affected by diseases or pests, but its sharp leaf edges can be a handling hazard.CC BY-SA 4.0