The vegetation of Jae Sawn National Park, Lampang Province
Maxwell, J. F., S. Elliott & V. Anusarnsunthorn, 1997. The vegetation of Jae Sawn National Park, Lampang Province, Thailand. Nat. Hist. Bull. Siam Soc. 45(1): 71-97.
Contributors
After joining CMU's Biology Department in 1992, Ach. Max embarked on prolific and exhaustive plant-species inventories of several of northern Thailand's mountains, expanding the department's herbarium (CMUB) and establishing its innovative (at that time) computerized flora database. In defining the natural states of various indigenous forest types, this work was invaluable when FORRU-CMU was establishing, defining restoration goals and guiding species selection for restoration trials. This paper presents the results of such a survey of Doi Khuntan. Using the database to analyse the flora, the species composition of the mountain's various forest types and the phenology of plants by habit are presented. It provides an historical snapshot of the park's condition towards the end of the 20th century. A similar treatment of Doi Khuntan National Park is here.
ABSTRACT: Research on the botanical diversity, vegetation, and floristics of Jae Sawn National Park was started by Herbarium staff of the Department of Biology, Chiang Mai University in August 1995. The vegetation in the lowlands (300 to c. 800 m elevation) includes bamboo + deciduous (teak) and deciduous dipterocarp-oak facies, while from c.800 to 1,000 m elevation, the forest is mixed evergreen + deciduous hardwood. Above this is primary evergreen, seasonal, hardwood forest, mainly at 1,000-1,500 m elevation and from 1,800 to 2,031 m (Doi Lahnggah), the highest peak in the national park. From c. 1,250 m elevation upwards, and particularly at 1,500-1,800 m, the forest is mostly primary evergreen hardwood + pine (Pinus kesiya Roy. ex Gord.,Pinaceae). Most of the park is on granite bedrock, while shale is found in scattered lowland areas up to c. 750 m elevation and shale with phyllite in the Doi Lahnggah area. The northern part of the park is on limestone, where many calciphytes are found. Seven new records for the flora of Thailand have also been found. A computer database, containing taxonomic, distributional and ecological information on all 1,353 species of vascular plants recorded, as of 1 March 1997, has been prepared, including 344 tree species, 136 treelets, 106 woody climbers, 58 shrubs, 447 vines and 562 herbs. The database clearly identified primary evergreen forest and mixed evergreen + deciduous forest equally as the two most important habitats in the park, for maintenance of overall botanical diversity and as the main repository of rare and threatened species. In combination, they support 83% of the park's entire flora. The species most in danger of extirpation from the park and most in need of immediate conservation measures include Podocarpus neriifolius D.Don (Podocarpaceae), Epirixanthes elongata BI. (Polygalaceae), and Cycas pectinata Griff. (Cycadaceae).