Effects of grazed stubble height and timing of grazing on resprouting of clipped oak seedlings

Abstract

Although a number of studies have investigated the effects of grazing frequency and intensity on seedling resprouting, the influence of grazed stubble height and timing of grazing on oak seedlings is little known. In the present study, we aimed to explore the effects of grazed stubble height and timing of grazing on the seedling resprouting of twelve oak species. By imitating herbivory grazing, we artificially clipped the shoots to different stubble heights and at different development stages of seedlings to see the resprouting capability of 12 oak species. Our study showed that both grazed stubble height and timing of grazing posed significant influences on resprouting of clipped oak seedlings. Our results indicate that the attached cotyledons play an important role in supporting resprouting of the clipped oak seedlings. Moreover, oaks bearing larger acorns show higher ability to counter herbivory grazing than those producing smaller ones. Higher stubbles grazed by herbivores exert less negative impacts on resprouting of oak seedlings than lower stubbles. Earlier grazing is less harmful to damaged oak seedlings compared with later grazing by herbivory animals.