Briza Media

''Briza media'' is a perennial grass in the family Poaceae and is a species of the genus '' Briza''.

Common name includes quaking-grass, common quaking grass, cow-quake, didder, dithering-grass, dodder-grass, doddering dillies, doddle-grass, earthquakes, jiggle-joggles, jockey-grass, lady's-hair, maidenhair-grass, pearl grass, quakers, quakers-and-shakers, shaking-grass, tottergrass, and wag-wantons.

Description

''B. media'' flowers from June to September in the UK, and is characterised by its fine stems and distinctive hops-shaped green and purplish spikelets.Wildlife Trusts - Quaking Grass
/ref> The plant is a loosely tufted perennial with short rhizomes arising from vegetative shoots. The culms typically attain a height of 15 – 60 cm, while the hairless dull glaucous to mid-green leaves are usually 4 – 20 cm long, 2 – 4 cm wide. They possess minute forward-pointing hairs with a slender boat-shaped tip.

The loose, roughly pyramidal panicles are 4 – 10 cm long, with up to 20 branches and 60 spikelets. The spikelets are 4 – 7 mm long, loosely scattered and drooping, laterally compressed and elliptic to ovate in shape.

Distribution and habitat

This grass species is common in England and Wales but rare in northern Scotland. It is native and widely distributed in Britain and Europe, except for the extreme north. It is absent from Iceland, the Faroe Islands, the Isles of Scilly and the far north and south of Ireland.Dixon JM. 2002. Biological Flora of the British Isles: ''Briza media''. ''Journal of Ecology'' 90: 737 – 752.

In North America, the species has been introduced and occurs in Connecticut, Massachusetts, Michigan, and Vermont in the USA, and in British Columbia and Ontario in Canada.

Habitat and ecology

''B. media'' is a characteristic species of unimproved species-rich grassland, grazed calcareous grassland and pasture, fens, old meadows, scree slopes, quarry soils and roadside verges. Its seeds are consumed by many farmland birds. It is reported to be a poor competitor and therefore negatively impacted by a high density of neighbouring plants in unmanaged grassland. It appears able to tolerate a relatively high grazing regime

Predominantly a species of calcareous grassland, ''B. media'' occurs with a high constancy in multiple plant community types as defined by the National Vegetation Classification.Rodwell JS ed. 1992. ''British Plant Communities'' Vol. 3.
Grasslands and Montane Communities. Cambridge University Press, Cambridge, UK These include, but are by no means restricted to, CG1 ''Festuca ovina'' – ''Carlina vulgaris'' to the CG10 ''Festuca ovina'' – ''Agrostis capillaris'' – ''Thymus praecox'' as well as the mesotrophic MG3 ''Anthoxanthum odoratum'' – ''Geranium sylvaticum'' grasslands.

The plant is grazed by several insect species, including the larvae of '' Leptopterna ferrugata'', '' Apamea scolopacina'', ''Phytomyza nigra'', as well as the larvae and adults of ''Eriophyes tenuis'', causing leaf rolling and sterility.

Taxonomy

The subspecies ''Briza media'' subsp. ''media'' occurs throughout the species’ range, while subspecies ''elatior'' (Sibth. & Sm.) Rohlena occurs in southeast Europe.

There are no known hybrids.

It is distinguished from the closely related '' Briza maxima'' by the size of the flower spikelets.

Briza media - keskmine värihein.jpg, Keila, Estonia
PNBT Briza media wiecha 03.07.10 pl.jpg, Bory Tucholskie National Park, Poland

References

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{{Taxonbar, from=Q164237

Pooideae
Grasses of Europe
Plants described in 1753
Taxa named by Carl Linnaeus