Abstract
This paper investigates the characteristics of succession in Lespedeza bicolor var. japonica Nakai and Amorpha fruticosa L. plant communities that were introduced into the same cut slope on the Nishiseto Expressway at Hakatajima by spraying with a soil/seed cultivative base. I have compared the results of 25 years after the application of soil/seed cultivative base with those of a thick cultivative base that was applied at the same time and place. The results of the study are as follows: 1)Natural invasion and growth of woody plant species began to increase from 17 years after the application of each type of cultivative base. 2)Leguminosae woody plants were more effectively promoted natural invasion of woody plant species with seed disposal by birds and small animals. 3)The soil/seed cultivative bases were more effective in promoting broad-leaved deciduous pioneer tree species and Pinus densiflora Sieb. et Zucc. trees. 4)The thickly sprayed cultivative base was more effective in promoting Ligustrum japonicum Tunb. and Quercus phyllyraeoides A. Gray such as broad-leaved evergreen tree species. However, it is quite likely that we can promote a more natural invasion of woody plant communities in areas sprayed with a thick cultivative base, rather than a soil/seed cultivative base, by 1)not developing mono-stratified woody plant communities, such as Lespedeza bicolor var. japonica and Amorpha fruticosa, and 2)in case of planning that introduce Leguminosae woody plants community, decrease the expectative numbers of germination will be drastically, or 3)developing a low-density multi-strata stratified woody plant community by revegetative works to establish a plant community such as that found 25 years after spraying with the soil/seed cultivative base.
