Fiorin, surface twitch, watergrass, white bent
Agrostis stolonifera L. (Agrostis alba var. stolonifera, A. palustris)
Perennial Grass Weeds
Creeping bent is a stoloniferous perennial grass that is native in damp arable fields and grassland, in gardens, on rough ground, in ditches and in many habitats by water. In early surveys of Bedfordshire, Hertfordshire and Norfolk, creeping bent was associated with all soil types and was common on chalk and gravel soils but less frequent on clay. It occurs on poorly drained soils of low or high pH, but prefers fertile soils of medium to heavy texture.
Creeping bent is abundant throughout Britain. In a study of seedbanks in some arable soils in the English midlands sampled in 1972-3, creeping bent seed was recorded in 41% of the fields sampled in Oxfordshire and 34% of those in Warwickshire. The seed was never present in large numbers.
Creeping bent is said to hybridise with common bent (A. capillaris). Ecotypes have developed with tolerance to heavy metals and to saline conditions. Cultivated forms are used on golf courses and putting greens. Creeping bent is relatively palatable to stock. The fungal cereal disease eyespot (Cercosporella herpotrichoides) has been recorded on creeping bent.
Creeping bent flowers from July to August. The flowers are wind pollinated and seed is set from August to October.
Creeping bent seedlings emerge in autumn and spring. Seed sown in field soil in pots showed no periodicity of emergence. Most seeds had gone after 18 months, germinating whenever conditions were favourable.
Creeping bent usually remains green throughout the year with long creeping stolons that overwinter.
Persistence and Spread
Creeping bent is unlikely to form a persistent seedbank in soil.
Vegetative spread is important leading to the formation of large clumps made up of a single clone. In favourable conditions it can spread rapidly forming dense mats that smother other plants.
Small infestations may be dug out to prevent further spread. Field cultivations with harrows should aim to gather up the roots and stems, which should then be burnt. Detached shoots can re-root following soil disturbance in arable fields.
In roadside verges, increasing the cutting frequency encouraged the occurrence of creeping bent. In undergrazed pasture it is suppressed by taller growing grasses. In a ryegrass sward, high applications of cow slurry favour creeping bent more than perennial ryegrass.
In laboratory tests, leachate from composted household waste decreased the germination of creeping bent seed. In pot tests, covering the seeds with up to 3 cm depth of compost reduced seedling emergence.
Updated October 2007.