Chamaecyparis obtusa var. formosana (Hayata) Hayata
Endemic to Taiwan where historically widespread logging has seriously depleted the population
Habitat and Ecology
Found in mixed coniferous or conifer-broad-leaved forest in the cool temperate coniferous forest belt at altitudes from 1800 to 3000 metres above sea-level with Chamaecyparis formosensis, Calocedrus formosana, Cunninghamia konishii, Taiwania cryptomerioides, Alnus henryi, Schima superba, Photinia davidiana, Rhododendron formosanum, Pasania sp., and the alpine bamboo Yushania niitakayamensis. Soils are relatively deep and well-drained loams or loamy sand. The climate is cool, very moist, with cloud-cover resulting in fog and rain much of the year and very high precipitation exceeding 4000mm per year.
There has been an estimated historic population reduction of over 30% within three generation lengths due to logging. This historic reduction may not be reversible due to ongoing decline in the quality of habitat due to reforestation with alternative taxa.
Logging has caused a considerable decline in many of the more accessible stands. After massive but unquantified destruction the total area of occupancy (in mixed stands with other conifers) 50 years ago, there was ca. 50,000 ha for C. obtusa var. formosana and C. formosensis combined (Lee,1962). It is almost certainly less than that now, as the decline of natural forest has continued from 66% to 52% of the land surface (Lu & Pan, 1996). Old growth forest is being replaced by secondary vegetation; where active reforestation is undertaken the emphasis is usually on faster growing conifers (Cryptomeria, Cunninghamia, Pinus). Although logging of natural stands has now ceased, regeneration is limited.
Important stands are protected in the Yuanyang Lake Reserve. A logging ban has also been introduced.