Abstract
The Shiia-type forest, dominated by Shiia Sieboldi and S. cuspidata, is the representative association of the warm temperate climax in Japan and it is also the case in MATUYAMA8) district, located to the northwest of Sikoku. But the stands are found only as fragments in the precincts of shrines and temples, with rare exceptions of other natural residual forests.
The writer investigated this association from the standpoint of composition, physiog-nomy and macro-environment.
The altitudinal range of Shiia-type forest in this district is from 30 to 300m. above the sea-lever, covering the hill or the foot and sides of low-mountains. But the ridges where the soil is more drained is mainly covered by the pine forest (Pinion densiflorae), essentially different from the broad-leaved evergreen forest (Shiion Sieboldi). Shiia Sieboldi prefers the higher elevation with a more humid climate, While S. cuspidata is the more important species growing more abundantly and widely.
This association may be identical with Shiia Sieboldi-Bladhia japonica association established by Suzuki-Tokio from Izu and Bôsô Peninsula. The characteristic species in MATUYAMA District are as follows :
Shiia cuspidata (X: 8376), Dryopteris erythrosora (VII: 377), Shiia Sieboldi (III: 522), Cyclobalanopsis glauca (IX: 545), Ilexintegra (IV: 27), Symplocos prunifolia (IV: 241), Dendropanax trifidum (IV: 136), Bladhia japonica (VII: 260), Ophiopogon japonicus (V: 16), Mitchella undulata (II: 199), Ternstroemia gymnanthera (VI: 69), Damnacanthus indicus (II: 53), Milletia japonica (V: 4).
On the Setouti coast, especially to the north of the center of TAKANAWA Peninsula, the development of this association is less vigorous, with the admixture of the Cyclobalanopsis glauca forest and the Quercus phylliraeoides forest. Besides, the Machilus Thunbergii forest cannot be found in this district. The absence of Machilustype forest as well as the poor development of Shiia-type dominants on Maqui-type might be attributed to the drier climate of SETOUTI region and the geological formation of granite.
