Planteværn Online > Skadevoldere - Weed biology<br> <sub>Agro-region: Denmark</sub> - Couch-grass
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25.4 2024 undefined

Weed biology
Agro-region: Denmark

Couch-grass Previous page Next page

Go to identification key for weeds

Can be mistaken for

Black-grass, which has no leaf teeth.

Characteristics

Early stages
Rolled vernation. The leaves are dull, rather slender and have hairy top sides. Dentated. Densely hairy leaf sheath. The ligule is very short, approx. 1 mm. The plants are characteristically reddish brown at the 1-2-leaf stage. Couch grass seedlings are somewhat slighter than shoots from bolters.

Mature plant
Couch grass is a high plant (50-120 cm) with erect stems. The spikelets are arranged in an open spike, where the surface of the spikelets faces the straw unlike Rye-grass where the edge of the spikelets faces the straw. The plant is especially known by the long, white subterranean bolters. Seed production: Up to approx. 50 seeds per spike.

Seed
Oblong, lancet-shaped, often slightly asymmetric. Sickle-shaped cross section. The bract is domed, but keeled towards the top of the middle vein, which continues as a short awn. The rachilla is somewhat patulous, short, flattened, with an oval, bowl-shaped head. The ventral furrow is deep and shaped like a halved tube. The surface is slightly rough with barbate side ribs on the bracteole. Thousand grain weight approx. 3.9 g.

Biology

Propagation and dispersal
Through subterranean bolters and seeds.

Habit
Perennial

Importance

The species is frequently found in all types of crops throughout Denmark. It is an extremely injurious weed causing losses in all crops. It is undesirable in a large number of seed grass crops because it is difficult to separate the seeds.

For treatment options, consult 'Herbicides Across'.
For more options, consult 'Main Menu'.

Taxonomy

Gramineae.

Names in different languages

Danish : Kvik, alm.
German : Gemeine Quecke
English : Couch-grass
Latin : Elymus repens
Norwegian : Kveke
Swedish : Kvickrot
Couch-grass: Very early stage
Very early stage
Couch-grass: Early stage
Early stage
Couch-grass: Leaf teeth
Leaf teeth
Couch-grass: Hairy leaf sheath
Hairy leaf sheath
Couch-grass: Flowering spikelets
Flowering spikelets
Couch-grass: Mature plant
Mature plant
Couch-grass: Seeds
Seeds
 
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