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Elymus repens

Elymus repens
Kweek Elytrigia repens.jpg
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
(unranked): Commelinids
Order: Poales
Family: Poaceae
Genus: Elymus
Species: E. repens
Binomial name
Elymus repens
(L.) Gould
Synonyms

Elymus repens, commonly known as couch grass, is a very common perennial species of grass native to most of Europe, Asia, the Arctic biome, and northwest Africa. It has been brought into other mild northern climates for forage or erosion control, but is often considered a weed.

Other names include common couch,twitch, quick grass, quitch grass (also just quitch), dog grass, quackgrass, scutch grass, and witchgrass.

It has creeping rhizomes which enable it to grow rapidly across grassland. It has flat, hairy leaves with upright flower spikes. The stems ('culms') grow to 40–150 cm tall; the leaves are linear, 15–40 cm long and 3–10 mm broad at the base of the plant, with leaves higher on the stems 2–8.5 mm broad. The flower spike is 10–30 cm long, with spikelets 1–2 cm long, 5–7 mm broad and 3 mm thick with three to eight florets. The glumes are 7–12 mm long, usually without an awn or with only a short one.

It flowers at the end of June through to August in the Northern Hemisphere.

Flower spike

Blunt ligule 1mm high, also showing a few very fine hairs of the plant

Showing the leaf is dull green, mainly parallel, with auricles and ribbed

Rhizomes

Showing general tufted and visual appearance of the plant

Various taxonomic subdivisions of this species have been proposed. Moreover, it is assigned to various genera (Elymus, Elytrigium, Agropyron). In a recent classification, three subspecies are distinguished, one of these with an additional variety:

Hybrids are recorded with several related grasses, including Elytrigia juncea (Elytrigia × laxa (Fr.) Kerguélen), Elytrigia atherica (Elytrigia × drucei Stace), and with the barley species Hordeum secalinum (× Elytrordeum langei (K. Richt.) Hyl.).


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Wikipedia

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