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

Observations to follow the development of 2-year-old oak seedlingstook place over a 6-year period at a fenced site within a maturestand of oak in southern England. Bramble and bracken were abundant,but the cover of other species was low. Although seedlings doubledin height, only 13 per cent survived and few were taller thaneither bramble or bracken. The initial number of seedlings wasinversely related to both canopy cover and distance to the nearestparent tree. The final number of seedlings could be predictedfrom the initial percentage covers of bramble and bracken, andeither the overstorey canopy cover or the initial number ofseedlings. The average annual rate of seedling mortality, whichwas 25–50 per cent, was significantly influenced by thevegetation present. Grass was positively related to survivalwhereas there was an inverse relationship with both brambleand bracken cover. Models estimated 80 per cent annual seedlingsurvival at 25 per cent bramble cover but only 50 per cent at60 per cent cover. Although grasses can be competitive species,results indicate that oak seedling establishment may be betterin areas with a ground flora comprising grass.