2023 Volume 23 Pages 31-37
Mt.Rokko, located in the northern part of Kobe City, is home to a large number of native species of the genus Hydrangea. Among them, Hydrangea serrata has high genetic diversity, with large regional and individual variation. Therefore, we conducted a survey of native habitats to understand the distribution and trait diversity of local individuals of Hydrangea serrata in the Rokko Mountains, and to collect and conserve rare mutant individuals. This study was conducted in collaboration with The Kobe Municipal Arboretum, which is located in the Rokko mountain range and has a large collection of Hydrangea species. However, the native habitats in the Rokko mountain distribution are not well known, and we intend to identify, protect, and cultivate the rare individuals. Additionally, we plan to identify the environmental conditions of the native habitats，cultivate the species，and exhibit in the Botanical Garden.The environmental conditions of the native habitats will also be used as a reference for the cultivation and display of Hydrangea serrata in the botanical garden. As a result of the survey, it was found that the native species grows at altitudes of 400 m or higher range in the Rokko mountain, widely in cedar forests, and scattered along streams, etc. Temperatures not exceeding 30℃, humidity of 80% or higher, northern slope, moderate sunlight through trees, slope, and valley shape were considered favorable conditions for growth.
