Vegetation of Southeast Asia Studies of Forest Types 1963-1965

also represented in each of the adjoining Mekong basin countries.
These are:-(a) Evergreen - separated into Rain, Moist, Dry Evergreen,
Montane, Coniferous and Swamp, including Mangrove; (b) Deciduous -
classified as Mixed, Dipterocarp, Beach', Thorn, Bamboo and Savanna.
Observations made on the ground and from the air, on the effect
of chemical defoliants on vegetation, conducted near Pranburi, upper
peninsular Thailand, under the direction of the Biological Laboratory
at Fort Detrick, Maryland, are discussed briefly.
Attention is drawn to some of the most prevalent plants in
Thailand, with wide distribution in Southeast Asia, and which are
considered hazardous, providing ideal sites for ambush along roadsides
and in forest clearings.
Stress is placed on the use of aerial surveys and photo sampling,
as a tool to supplement ground investigation or to expedite the
evaluation of the type of vegetation prevailing in a given area.
There is a review of field studies which have been in progress
throughout Thailand during the last 2 years by a Thai field team to
prepare profiles of tree stands, in order to determine the structure
and species composition of various forest associations, ranging from
the canopy to the ground cover. At the same time, soil samples are
gathered at different horizons for analysis.
A comparison is made between the major aspects of the topography,
climate and vegetation of Southeast Asia, Puerto Rico and Texas.
A series of maps illustrates the various forest zones investigated,
and the distribution of Evergreen and Deciduous forests occurring
in Thailand. One map indicates the range of the principal forest
types in North and South Vietnam, Cambodia and Laos.
Part II contains a series of 125 ground and aerial photographs,
most of which were taken by the author during thG recent field
assignments. These illustrate the principal forest types in Thailand,
which are representative of similar formations in the adjoining Mekong
basin countries; some of the most frequent weed plants in Southeast
Asia, providing sites for ambush in clearings and along highways;
aerial photographs of some of the major forest types in Thailand,
taken immediately following ground studies; and views of the effect
of chemical defoliants on vegetation near Pranburi, upper Peninsular
Thailand. A limited number of forest types occurring in South
Vietnam, Laos and Cambodia are also illustrated.
• Part III contains an annotated Bibliography, of almost 80O
titles, referring to forests, forest products, agricultural crops,
and other resources of Southeast Asia, with emphasis on Thailand.