The dry dipterocarp forest is a
deciduous forest distributed naturally on
mainland of Southeast Asia. This forest is
scattered in the area of monsoon climate
with a marked dry period more than four
months a year and total rainfall of 900-
1,200 mm. per year (Na lamphun et al.,
1969). Four dominant xeric dipterocarp
tree species are indicator of DDF; Shorea
obtusa, S. siamensis, Dipterocarpus
obtusifolius and D. tuberculatus.