|Abstract||Previous to the 4th UNESCO Expedition, Dr H. Sleumer of the Rijksherbarium made three trips together with Mr Tem Smitinand, first to Doi Chiengdao and Doi Suthep in the North (Aug. 15-21, 1963), then to the Khao Yai National Park in Central Siam (Aug. 28-29), then to Pha Nok Khao and Phu Krading South of Loie in NE. Siam (Sept. 8-11).|
The 4th UNESCO Training Expedition was conducted by Mr Tem Smitinand of the Royal Forest Department, Bangkok, and Dr H. Sleumer of the Rijksherbarium, the latter serving as only instructor. The 10 participants, from Vietnam (1), the Philippines (1), Malaya (2), Singapore (1), Indonesia (2) and Thailand (3) started from a base camp 44 km from the highway from Suratthani to Takuapa in the Peninsula on Sept. 19, 1963. They investigated the flora of 7 limestone hills in the region: Khao Phra Rahu, Khao Lek, Khao Wong, Khao Ne Dang, Khao Pak Chawng, Khao Lang Tao, Khao Dai Kuad, ranging in altitude from 180 to 500 m. Each of these hills had a few peculiar species which were not found on the other hills, although in general the flora, especially in the lower slopes, was the same; 156 herbarium numbers with duplicates were here collected.