Development of Quercus robur advance regeneration following canopy reduction in an oak woodland

Abstract

Observations to follow the development of 2-year-old oak seedlings took place over a 6-year period at a fenced site within a mature stand of oak in southern England. Bramble and bracken were abundant, but the cover of other species was low. Although seedlings doubled in height, only 13 per cent survived and few were taller than either bramble or bracken. The initial number of seedlings was inversely related to both canopy cover and distance to the nearest parent tree. The final number of seedlings could be predicted from the initial percentage covers of bramble and bracken, and either the overstorey canopy cover or the initial number of seedlings. The average annual rate of seedling mortality, which was 25-50 per cent, was significantly influenced by the vegetation present. Grass was positively related to survival whereas there was an inverse relationship with both bramble and bracken cover. Models estimated ∼80 per cent annual seedling survival at ∼25 per cent bramble cover but only 50 per cent at ∼60 per cent cover. Although grasses can be competitive species, results indicate that oak seedling establishment may be better in areas with a ground flora comprising grass. © Institute of Chartered Foresters, 2007. All rights reserved.