2013 Volume 39 Issue 3 Pages 422-428
In order to restore a broadleaved forest, different seral stage broadleaved trees were planted using the so-called “natural planting” technique on post-stone pit slope adjacent to the Iwaigawa dam. The purpose of this study was to confirm whether the initial vegetation, in which pioneer species are dominant, and vertical forest structure have developed. A survey was performed for the following trees: Rhus sylvestris Sieb. et Zucc., Prunus pendula Maxim. f. ascendens (Makino) Ohwi, Rhus succedanea L., Prunus jamasakura Sieb. ex Koidz., Zelkova serrata (Thunb.) Makino, Acer palmatum Thunb., Abies firma Sieb. et Zucc., Camellia japonica L., and Ilex integra Thunb.; 43 species were planted within patches surrounded by deer fences. In 2011, the survival percentage of the planted trees was 66.1%. The number of individual trees was compared on the basis of height class by using data collected in 2009 and 2011, and most of the pioneer and middle seral-stage species were moved to a higher class. Late successional species were observed to be in the low height class in both years. Clear differences were found for the canopy area rate in each seral stage: pioneer species, 59.0%; middle seral-stage species, 36.1%; and late successional species, 4.9%. The dominance of pioneer species in the canopy layer was successfully confirmed using a crown projection diagram. On the basis of these results, we concluded that the initial vegetation had developed in the multi-layered forest.