Glyceria maxima

Glyceria maxima

The great manna grass or Gliceria major (Glyceria maxima, Hartm. Et Holmb., 1919) is a herbaceous species belonging to the Poaceae family.

Systematic –
From a systematic point of view, it belongs to the Eukaryota Domain, Plantae Kingdom, Tracheobionta Subregion, Spermatophyta Superdivision, Magnoliophyta Division, Liliopsida Class, Commelinidae Subclass, Cyperales Order, Poaceae Family, Pooideae Subfamily, Meliceae Tribe and therefore to the Genus Glyceria and the Species G max. .
The following terms are synonymous:
– Catabrosa hydrophila Link;
– Exydra aquatica (L.) Endl .;
– Festuca aquatica (L.) Mutel;
– Glyceria altissima Garcke;
– Glyceria aquatica var. scabra Peterm .;
– Glyceria maxima f. acute (Peterm.) Soó;
– Glyceria maxima f. scabra (Peterm.) Soó;
– Glyceria spectabilis Mert. & W.D.J.Koch;
– Glyceria spectabilis f. acute Peterm .;
– Heleochloa aquatica (L.) Drejer;
– Heleochloa aquatica (L.) Fr .;
– Hydrochloa aquatica (L.) Hartm .;
– Hydropoa spectabilis (Mert. & W.D.J.Koch) Dumort .;
– Melica aquatica (L.) Weber ex P. Beauv .;
– Molinia maxima Hartm. (Basionym);
– Panicularia aquatica (L.) Kuntze;
– Poa aquatica L.

Etymology –
The term Glyceria comes from the Greek sweet, lovable γλῠκ amς glycýs.
The specific epithet maxima is the superlative of magnus grande: maximum, the largest, for the dimensions compared to those of the congenital species.

Geographical Distribution and Habitat –
The great manna grass is a species with a large circumboreal distribution present in almost all regions of Italy (it is missing in the Aosta Valley, Puglia, Basilicata and Calabria).
Its habitat is that inside the ditches, in the marshes, along the banks of the rivers, on periodically flooded muddy soils, below the mountain belt.

Description –
Glyceria maxima is an aquatic herb that often takes on a weed character.
It has erect, or slightly arched, stems that start from large rhizomatous or stoloniferous roots, which tend to form large tufts, very dense and dense.
The stems grow up to 50-100 cm, are green, or bluish green.
The leaves are linear, a few millimeters wide, rough and rigid, green in color.
At the apex of the stems, in the summer there are thin panicles made up of small flowers, followed by the small elongated seeds. Sometimes the submerged stems of these specimens root to the internodes.
The flowering period is between July and August.
The fruit is a 1.5-2 mm ellipsoid karyoxide, 2/10 long embryo of the karyoxide and linear hilum as long as the karyoxide. 5-7flore spikelets, streaked with brown, lanceolate, compressed laterally, of 2 x 7-8mm, which disarticulate when ripe over the glumes and under each fertile flower. Persistent subequal glumes of 2.5 mm. Lemons of 2.5-3 mm.

Cultivation –
Glyceria maxima plants are very vigorous and can be planted both in the sun and in the shade; the glyceria maxima are not afraid of the cold and can even withstand temperatures close to -20 ° C, although often during the winter they go to vegetative rest and the aerial part dries completely.
They don’t even fear the summer heat. They are planted near the aquatic gardens, on the banks of bodies of water, or even submerged; over the years they tend to form large colonies, it is therefore good to keep the tufts contained, to prevent them from invading the pond or the lake in which they were placed, becoming a weed variety that is difficult to contain.
They grow without problems in any terrain, even constantly submerged by stagnant water; in general, when plants are placed in very rich and soft soils, they tend to become pests very quickly. These aquatic plants can also develop in emerged soils, as long as they are close to waterways so as to have a high degree of humidity which allows the development of this kind of shrubs.
It is good to check that the area in which these plants are grown has a soil capable of maintaining good humidity, otherwise the development of these shrubs will be rather limited.
As for watering, as it is easy to imagine, being an aquatic variety, this genus of plant needs a constant supply of water, provided that it is not already inside a pond or submerged soil. If it is grown in a container, it is necessary to check that the humidity always remains quite high, with the foresight to replace the stagnant water present in the container on a regular basis, every 15/20 days.
The multiplication of the Gramignone major, to obtain new specimens, usually takes place by division; it is possible to take portions of the tufts, or the basal shoots that normally develop at the foot of the plant. Given the high diffusion and ease of propagation of this kind of plant, it is very easy to obtain new seedlings.

Uses and Traditions –
Glyceria maxima, or great manna grass, but better known as marsh grass is a marsh grass plant that forms thick tufts of bright green color suitable for the banks of ponds and phytodepuration.
For this reason it can be inserted, with due evaluations, within phytodepuration plants, with a very important function of both physical and biochemical purification.
It is important to first ensure that the humidity, soil and climatic characteristics correspond to the needs of this plant.
Glyceria maxima is also used for ornamental lawns, where the soil and climatic conditions are optimal.

Method of Preparation –
In addition to the ornamental uses and as a phytodepuration plant, no relevant uses are known for Glyceria maxima.

Guido Bissanti

Sources
– Acta Plantarum – Flora of the Italian Regions.
– Wikipedia, the free encyclopedia.
– Treben M., 2000. Health from the Lord’s Pharmacy, Tips and experiences with medicinal herbs, Ennsthaler Editore
– Pignatti S., 1982. Flora of Italy, Edagricole, Bologna.
– Conti F., Abbate G., Alessandrini A., Blasi C. (edited by), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.

Warning: Pharmaceutical applications and alimurgical uses are indicated for information purposes only, they do not in any way represent a medical prescription; therefore, no responsibility is accepted for their use for healing, aesthetic or food purposes.