A stage in the cyclical pattern of changes that is typical of many plant and heathland communities, including forest grasslands and heaths. In grassland, the term refers to the accumulation of wind-borne particles to form a small hummock around any grass seedling that chances to invade a hollow, which in turn results from the erosion of a former hummock in the degenerate phase. In heathlands, the term describes the bushy phase of growth in individual Calluna vulgaris (heather) plants, lasting from about 7 to 13 years of age. At this stage net primary production in the new shoots is at a maximum and the dense, bushy plant allows little light to reach the ground, hence it tends to suppress other species commonly associated with C. vulgaris in the pioneer, mature, and degenerate phases. See also mosaic evolution. Compare degenerate phase; hollow phase; mature phase; pioneer phase.
Subjects: Plant Sciences and Forestry — Ecology and Conservation.