Glyceria fluitans
Glyceria melicaria
floating mannagrass, floating sweet-grass, glycerie flottante, water manna grass
glycerie melicaire, melic mannagrass, northeastern manna grass
20-150 cm tall, 2-4 mm thick, erect or spreading, sometimes decumbent and rooting from the lower nodes, distal portion sometimes floating in shallow water.
50-100 cm tall, 3-5 mm thick, erect.
glabrous, keeled;
ligules 5-15 mm;
blades 5-25 cm long, 3-10 mm wide, both surfaces smooth.
smooth, not or only weakly keeled;
ligules 0.2-0.9 mm, translucent, rounded to truncate;
blades 25-40 cm long, 2-7 mm wide, abaxial surfaces smooth, adaxial surfaces scabridulous.
10-50 cm long, 2-3 cm wide;
branches 3-5 cm, paired or solitary, usually appressed to ascending, divergent at anthesis, with 1-4 spikelets;
pedicels 0.8-20 mm.
15-25 cm long, 0.8-1.5 cm wide, linear, nodding;
branches 5-9 cm, appressed, scarcely surpassing the node above, with 30-60+ spikelets;
pedicels 0.5-2 mm.
(15)18-39 mm long, 1.7-3.3 mm wide, cylindrical and terete, except slightly laterally compressed at anthesis, rectangular in side view, with 8-16 florets.
3.5-5 mm long, 1-2.5 mm wide, laterally compressed, oval in side view, with 3-4 florets.
lanceolate, veins terminating below the apices, apices acute;
lower glumes 1.3-2.4 mm;
upper glumes 1.7-3 mm;
rachilla internodes 0.4-0.6 mm;
lemmas 1.9-2.8 mm, smooth or scabridulous, 5-7-veined, veins raised, apices acute, prow-shaped;
paleas slightly shorter to slightly longer than the lemmas, lengths 2.5-4 times widths, keels well developed, not winged, tips incurved, narrowly notched between the keels;
anthers 2, 0.3-0.5 mm.
1.3-3.9 mm;
upper glumes 2.7-5 mm;
rachilla internodes 1.9-2.5 mm;
lemmas 5.2-8 mm, midveins extending to within 0.1 mm of the apical margins, scabrous over and between the veins, prickles about 0.05 mm, apices acute, usually entire;
paleas from shorter than to 0.6(1.5) mm longer than the lemmas, keels winged, apices bifid, teeth 0.1-0.4 mm, parallel to convergent, sometimes crossing when dry;
anthers 1.5-3 mm, usually purple.
2-3 mm.
1-1.5 mm;
hila subequal to the caryopses.
= 40.
= 40.
Glyceria fluitans
Glyceria melicaria
Glyceria fluitans is a Eurasian species. In the Americas, it has been collected from British Columbia to California on the west coast, in South Dakota, and from Newfoundland to Pennsylvania on the eastern seaboard. In Europe, it grows in rich, organic, wet soils, often near G. notata, with which it hybridizes. It is less tolerant of trampling than G. notata. Many earlier reports from eastern Canada are based on G. borealis or G. septentrionalis (Dore and McNeill 1980; Scoggan 1978). In western North America, it has been confused with G. xoccidentalis. It tends to differ from all three in its longer lemmas and anthers. Nevertheless, identification of some specimens will prove troublesome. For further discussion, see under the species mentioned.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Glyceria melicaria grows in swamps and wet soils. Its range extends from southeastern Ontario east to Nova Scotia, south to Illinois and the northeastern United States and, in the Appalachian Mountains, to northern Georgia. Glyceria xgatineauensis Bowden is a sterile hybrid between G. melicaria and G. striata. For further comments, see p. 77.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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