Glyceria ×occidentalis

Western manna grass, Western Manna Grass

Family: Poaceae · Type: perennial · Not Native

Western manna grass is a naturalized perennial herb found in northwestern California, northern Sierra Nevada, Sacramento Valley, central Coast, and San Francisco Bay Area in freshwater marshes, ponds, and streams at elevations below 1,300 meters. Flowering from June to August, this grass produces small spikelets in narrow inflorescences 15 to 40 centimeters long. Growing 70 to 150 centimeters tall with stems 1.5 to 2 millimeters in diameter, it often forms floating mats in aquatic environments. Its leaves feature ligules 5 to 12 millimeters long and blades 20 to 30 centimeters in length, typically 4 to 13 millimeters wide. Each spikelet contains 6 to 13 florets with lemmas 4.5 to 6 millimeters long, whose tips can be entire, dentate, or crenate.

Habitat: Freshwater marshes, ponds and streams

Bloom period: Jun-Aug

Elevation: < 1300 m

Bioregions: NW, n SNH, ScV, CCo, SnFrB

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.