Plant species diversity and mechanisms determining its variation have long been the subject of research, and are still debated in biogeography and ecology. High plant species diversity in tropical rain forests and its decreasing trend along the latitude and associated decrease in annual solar energy input and net primary production are well known. Greater physiographical heterogeneity in eastern Asia is also likely to explain greater biodiversity in this region compared to similar biomes at similar latitudes of eastern North America. Here I review climate patterns and kinds and frequencies of natural disturbances, and propose that interaction of climate and natural disturbances likely to have created different types of deciduous broadleaf forests (Cool Deciduous Forest [CDF] and Warm Deciduous Forest [WDF] of Nakashizuka and Iida) and/or mixed deciduous broadleaf-conifer forest (Cool Mixed Forest [CMF] of Nakashizuka and Iida) not only in eastern Asia, but also at similar latitudes of eastern North America at similar configurations. Therefore, presence of three major types of temperate forests (i.e. CDF, WDF, and CMF) at the eastern portion of the continents at mid-latitudes is likely to be a general phenomenon, and their patterns of distribution are likely to be determined by the interplay between climate and characteristics of natural disturbances.