Fuirena coerulescens, commonly known as the blue umbrella-sedge, is a perennial herbaceous plant belonging to the sedge family, Cyperaceae. This species is recognized for its distinctive blue-green foliage and its ecological role in wetland environments. As a member of the genus Fuirena, it shares characteristics with other sedges, which are grass-like plants often found in moist or wet habitats. The growth habit of Fuirena coerulescens is clump-forming, typically reaching heights of 30 to 60 centimeters. Its stems are erect and triangular in cross-section, a common characteristic of sedges. The leaves are linear, grass-like, and arranged alternately along the stem, often exhibiting a glaucous or bluish hue, which contributes to its common name. The inflorescence is a terminal spike or a series of spikes, bearing small, inconspicuous flowers. Each flower is subtended by a bract. The fruit is a small achene, which is the characteristic dry, one-seeded fruit of sedges. The root system is fibrous, anchoring the plant firmly in its substrate. Fuirena coerulescens is native to the southeastern United States, with its range extending from the coastal plain of North Carolina south to Florida and west to eastern Texas. It thrives in a variety of wet habitats, including freshwater marshes, swamps, ditches, and the edges of ponds and streams. It prefers full sun to partial shade and consistently moist to wet soils. While it is adapted to wetland conditions, it can tolerate periods of inundation. Cultivation is generally limited to specialized wetland gardens or restoration projects, as it requires consistently moist conditions to flourish. Ecologically, Fuirena coerulescens plays a role in stabilizing wetland soils and providing habitat for various invertebrates and small vertebrates. Its seeds and foliage may be consumed by some wildlife. While not widely cultivated for ornamental purposes, its unique blue-green coloration can add visual interest to water gardens or naturalistic plantings. There is no significant documented use of Fuirena coerulescens in agriculture, medicine, or culinary practices. An interesting characteristic of Fuirena coerulescens is its ability to tolerate waterlogged soils, a testament to its adaptation to wetland environments. The triangular stems are a key feature for distinguishing sedges from grasses, which typically have round stems. The blue-green coloration of the leaves is a result of a waxy cuticle, which can help reduce water loss and protect the plant from intense sunlight in its open, often sunny, wetland habitats. This adaptation allows it to thrive in conditions where many other plants would struggle.