degenerate phase

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degenerate phase The stage in the cyclical pattern of changes typical of grassland and heathland communities. In grassland, the term refers to the extended colonization by lichens of the small, grassy hummocks of the mature phase. As the frequency of soil-binding grass plants declines, erosion of the hummocks starts and a new cycle begins. In heathland, the term refers to Calluna vulgaris plants that are 20, 30, or more years old. A gap appears and widens gradually in the centre of the C. vulgaris bush, which becomes very straggly, with new shoots confined to the branch tips. In the gap and on the bare central stems lichens, especially Cladonia species, and mosses colonize. Eventually new C. vulgaris seedlings invade the central gap and a new cycle begins. Compare BUILDING PHASE; HOLLOW PHASE; MATURE PHASE; and PIONEER PHASE.

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degenerate phase The stage in the cyclical pattern of changes typical of grassland and heathlandcommunities. In grassland, the term refers to the extended colonization by lichens of the small, grassy hummocks of the mature phase. As the frequency of soil-binding grass plants declines, erosion of the hummocks starts and a new cycle begins. In heathland, the term refers to Calluna vulgaris plants that are 20, 30, or more years old. A gap appears and widens gradually in the centre of the C. vulgaris bush, which becomes very straggly, with new shoots confined to the branch tips. In the gap and on the bare central stems lichens, especially Cladonia species, and mosses colonize. Eventually new C. vulgaris seedlings invade the central gap and a new cycle begins. Compare building phase; hollow phase; mature phase; and pioneer phase.

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