Abstract
I evaluated changes in understory vegetation inside and outside deer-proof fences over 10 years after the exclusion of sika deer browsing pressure in 4 forest floor community types (short herb, tall herb, Sasamorpha borealis, and Sasa hayatae types) in cool temperate deciduous forests of the Tanzawa Mountains, central Japan, and examined whether understory vegetation damaged by sika deer changed to a state showing negligible influences of sika deer inside deer-proof fences. As a result, each forest floor type showed increases in the vegetation cover and species number of shrub layer inside deer-proof fences 10 years after their installment. In Sasamorpha borealis type, the cover of Sasamorpha borealis of shrub layer increased sharply inside deer-proof fence. Though changes in the species composition of herb layer differed among the forest floor types, the areas inside the fences as a whole showed an increase in tall perennial herbs and decreases in short perennial and non-palatable herbs. In addition, species endangered by sika deer appeared in the tall herb type. Outside the fences, annual grasses (Poaceae) and short perennial herbs increased after 10 years, while the vegetation cover or species richness did not decrease. Based on these results, I concluded that understory vegetation damaged by sika deer in cool temperate deciduous forests of the Tanzawa Mountains changed to a state showing negligible influences of sika deer 10 years after the exclusion of this browsing pressure.
