About Holcus mollis L.
Holcus mollis L. is a rhizomatous perennial grass that grows in woods and hedgerows, reaching 50 centimetres (20 in) in height. Its rhizomes typically grow around 5 cm (2.0 in) deep in soil, and sometimes grow even deeper. Rhizome growth takes place between May and November, with the fastest growth occurring from mid-June to mid-July. The rhizomes hold many dormant buds that will not develop unless the rhizomes are disturbed; after disturbance, new fresh aerial shoots can grow from broken rhizome fragments. This species flowers from June to July. The main features that distinguish it from Holcus lanatus are the presence of rhizomes, and the bearded nodes (often called 'hairy knees') on the culm. Holcus mollis grows best in woodland clearings and during the early stages of coppicing. Its growth and flowering become limited as the tree canopy develops. It is often a relict species of former woodland vegetation; even though it prefers shade, it can survive in open grassland and grassy heaths after woodland is cleared. It grows mostly on moist, freely-drained acid soils that are normally light to medium in texture and high in organic matter. It does not grow in areas with calcareous or base-rich soil, and it often grows alongside bracken.
