Glyceria

Glyceria is a widespread genus of grass family common across Eurasia, Australia, North Africa, and the Americas.
Glyceria is known commonly as mannagrass in the United States, or, in the UK, sweet-grass. These are perennial rhizomatous grasses found in wet areas in temperate regions worldwide. The base of the grass grows along the ground and may root at several places. Then it grows erect and bears leaf blades which may be flat or folded. The panicle inflorescences nod when heavy. Some mannagrasses are considered weeds while others are endangered in their native habitats.
Species
Glyceria acutiflora - creeping mannagrass - China, Korea, Japan, northeastern + east-central USA
Glyceria alnasteretum - Alaska, Russian Far East, Japan, Korea
Glyceria × amurensis - Amur Oblast
Glyceria arkansana - Arkansas mannagrass - south-central USA
Glyceria arundinacea - Eurasia from Hungary to Korea
Glyceria australis - Australian sweetgrass - Australia
Glyceria borealis - northern mannagrass - western, north-central, + northeastern USA incl Alaska; Canada incl Yukon + Northwest Territories; Mexico (Chihuahua)
Glyceria canadensis - rattlesnake mannagrass, Canadian mannagrass - Canada; USA (Northeast, Great Lakes, Oregon, Washington)
Glyceria caspia - Caucasus
Glyceria chinensis - China (Yunnan, Guizhou)
Glyceria colombiana - Colombia
Glyceria declinata - waxy mannagrass, low glyceria, small sweet-grass - Europe, Morocco, Madeira, Azores, Canary Islands; naturalized in scattered locales in North America
Glyceria depauperata - Japan, Kuril Islands
Glyceria × digenea - France, Czech Republic
Glyceria drummondii - Western Australia
Glyceria elata - tall mannagrass - western USA, British Columbia, Alberta
Glyceria fluitans - water mannagrass, floating sweet-grass - Morocco; Eurasia from Iceland + Portugal to Turkmenistan
Glyceria × gatineauensis - Québec, New York, West Virginia
Glyceria grandis - American mannagrass - USA incl Alaska; Canada incl Yukon + Northwest Territories
Glyceria insularis - Tristan da Cunha
Glyceria ischyroneura - Japan, Kuril Islands, Korea
Glyceria latispicea - New South Wales
Glyceria leptolepis - Russian Far East, China incl Taiwan, Korea, Japan
Glyceria leptorhiza - Korea, Honshu, Hokkaido, Heilongjiang, Amur Oblast, Khabarovsk, Zabaykalsky Krai
Glyceria leptostachya - davy mannagrass, narrow mannagrass - California, Oregon, Washington, British Columbia, Alaska
Glyceria lithuanica - Lithuanian mannagrass - northern Eurasia from Norway to Korea
Glyceria maxima - reed mannagrass, English watergrass, reed sweet-grass - Eurasia from Ireland to Xinjiang
Glyceria melicaria - melic mannagrass - eastern North America
Glyceria multiflora - Chile, Argentina, Uruguay, Rio Grande do Sul, Santa Catarina
Glyceria nemoralis - Caucasus, central + eastern Europe
Glyceria notata - marked glyceria, plicate sweet-grass - Eurasia + North Africa from Denmark + Morocco to Xinjiang
Glyceria nubigena - Great Smoky Mountain mannagrass - Great Smoky Mountains of North Carolina + Tennessee
Glyceria obtusa - Atlantic mannagrass - eastern North America
Glyceria occidentalis - northwestern mannagrass - California, Oregon, Washington, British Columbia, Idaho, Nevada
Glyceria × ottawensis - Ontario
Glyceria × pedicellata - northern + central Europe
Glyceria pulchella - MacKenzie Valley mannagrass, beautiful glyceria - Alaska, western Canada incl Yukon + Northwest Territories
Glyceria saltensis - Salta Province in Argentina
Glyceria septentrionalis - floating mannagrass - eastern USA, eastern Canada, northeastern Mexico
Glyceria spicata - India, Mediterranean
Glyceria spiculosa - eastern Russia, northern China, Korea
Glyceria striata - fowl mannagrass, ridged glyceria - Canada incl Arctic Territories, USA incl Alaska, Mexico, Guatemala
Glyceria × tokitana Masamura - Japan
Glyceria tonglensis C.B.Clarke - Himalayas, China incl Tibet
formerly included
Numerous species now considered better suited to other genera: Arctophila Catabrosa Colpodium Dryopoa Eragrostis Hydrocotyle Melica Phippsia Poa Puccinellia Scolochloa Torreyochloa Triplasis
References
Poaceae genera
Grasses of Africa
Grasses of Asia
Grasses of Europe
Grasses of North America
Grasses of Oceania
Grasses of South America