Effect of Acorn Burying Depth on Germination, Seedling Emergence and Development of Quercus aliena var. acuteserrata Comparison of Seedling Recruitment and Establishment of Quercus wutaishanica in Two Habitats in Dongling Mountainous Area, Beijing Growth and Morphological Structure of Trapa acornis Seedlings Effect of burial and environmental factors on seedling recruitment of Quercus liaotungensis Koidz Spatial and Temporal Patterns of Quercus liaotungensis Acorn Predation by Vertebrates in Dongling Mountain, Northern China Utilizable value of wild economic plant resource-acorn kernel Effects of relative abundance of Quercus mongolica acorns on five tree species seed dispersal in Xiaoxing’an Mountains, Northeast China. A STUDY ON THE ROOT SYSTEM OF TRAPA ACORNIS NAKAI