Poa nemoralis

Grove bluegrass ( Poa nemoralis )

The grove bluegrass ( Poa nemoralis ) is a species of the genus bluegrasses ( Poa ), belongs to the family of grasses ( Poaceae ). It is widely used in Europe and northern Asia, in North America there are naturalized occurrence as well as the closely related, by some authors as a subspecies of the guided - grove bluegrass Poa interior. Because of its characteristic horizontal projecting leaves, similar to an outstretched arm, it is sometimes called "Signpost grass ".

It is occasionally used as a component of shade grass mixtures.

Description

The grove bluegrass is a perennial herbaceous plant that grows horst -like and up to 80 centimeters reached heights of growth from 20 to 50, according to other data. The root system is flat. The leaf blade is 1 to 2 millimeters wide, in addition to the blade central rib each have a longitudinal groove visible. The blade tip is contracted rarely hood -shaped. The base of the leaf has no eyelashes, the ligule ( ligule ) is white, it is short and ends trimmed. Striking is the horizontally projecting lamina of the top sheet, it is the same length as the leaf sheath.

The wenigblütige, Rispige inflorescence is inclined at its tip slightly. The individual spikelets are 4-5 mm long and contain only one, according to other authors 2-5 hermaphrodite flowers. The lemma is hairy and green, this and the glumes are distinctly keeled. Awns are absent.

The flowering period is specified for Central Europe from June to July, the Flora of China called May-June in Sweden extends the bloom season from July to September.

Ecology

By infestation with the fungus Epichloe typhina white, later muffartige cases can the grove bluegrass, sometimes also in other species, occur around the stem.

Occurrence

In the Alps the grove bluegrass rises up to 2000 meters altitude, in China it occurs at altitudes 1000-4200 meters. The grove bluegrass is generally in deciduous forests, especially on thin places to see along the woods or in hedges. It prefers fresh soils that are rich in nutrients, humic and only moderately acidic.

Systematics and chromosome numbers

The grove bluegrass was first published in 1753 by Carolus Linnaeus in the first volume of Species Plantarum on page 69. The Style epithet nemoralis is in Latin, the adjective of nemus, " grove, wood".

Various families of the grove bluegrass can be distinguished by the number of chromosomes. Frequently come 2n = 28 and 42 before, also 2n = 14, 35, 56 and 70 were counted. The grove bluegrass forms with related species variable and difficult to distinguish hybrids, which can multiply by agamospermy, such as the marsh - meadow grass ( Poa palustris), the blue-green bluegrass ( Poa glauca ), with Poa versicolor nemoraliformis and Poa.