Aquatic plants with submerged and floating leaves: Glyceria fluitans, Ranunculus peltatus, Nymphaea (Nuphar) - lutea, Callitriche stagnalis, Potamogeton polygonifolius.
Sea-aster flourishes in the Wadden of Friesland and Groningen, the Dollart and the Zeeland estuaries, giving place nearer the shore to sandspurry (Spergularia), or sea-poa or floating meadow grass (Glyceria maritima), which grows up to the dikes, and affords pasture for cattle and sheep. Along the coast of Overysel and in the Biesbosch lake club-rush, or scirpus, is planted in considerable quantities for the hat-making industry, and common sea-wrack (Zostera marina) is found in large patches in the northern half of the Zuider Zee, where it is gathered for trade purposes during the months of June, July and August.
Water-cress, sweet flag, flowering rush, several potamogetons, water milfoil, water ranunculus, and the reedy sweet watergrass (Glyceria aquatica) rank amongst the criteria of excellence.
R, Alopecurus; a Bromus; 3, Arrhenatherum; 4, Glyceria; 5, Melica; 6, Mibora; 7, Nardus.
Glyceria fluitans, manna-grass, socalled from the sweet grain, is one of the best fodder grasses for swampy meadows; the grain is an article of food in central Europe.