Abstract: he analysis on the process of leaf birth and death of Juglans mandshurica, Fraxinus mandshurica and Phellodendron amurense shows that the birth of their leaves was a gradual process, with a duration of 40～60 days. The leaves born in different periods formed a distinct age class structure. The growth process of leaflet basically revealed an Stype curve. The death of leaves was distinguished into leaflet, with little litterfall and slow speed. Then, the compound leaves began to fall, and the quantity of defoliation increased and the speed quickened. The whole defoliation continued for 30～35 days. The process of leaflet fall was a Deevey Type Isurvival curve, and the compound leaves, a Type Ⅱ.

Key words: Population, Leaf demography, Birth and death process, Growth, Litterfall, Survival curve, Nipponia nippon, road, Maxent model, breeding habitat