AERIAL PHOTOGRAPHY AND FORESTRY IN ASIA 
matic film in combination with yellow filter. 
The photographic quality was in general 
good. 
For military purposes large-scale photog- 
raphy at a scale of 1:5,000 to 1:20,000 was 
made along roads and railway tracts, in the 
neighborhood of airfields, and in other par- 
ticular areas important for local military ac- 
tivities. 
(Up to the present only 40,000 photographs 
have been worked on for forestry purposes.) 
Based upon this material Mr. Rollet was able 
to make a vegetation map of South Vietnam 
at a scale of 1:400,000 for a total area of 
170,000 sq. km. Recently he also produced 
a vegetation map of a part of Cambodia 
situated east of the Mekong river. This map 
was also based upon the same photographic 
material and using the same identification 
system, in total about 55,000 sq. km. 
New vertical photography is currently be- 
ing carried out in the area by an American 
agency, size 9 by 9 inch, photo-scale 1 :40,000, 
panchromatic film, in combination with a 
yellow filter. Photographic quality is good; 
prints are made in semi-matt. This photogra- 
phy already covers the whole country of 
Cambodia, the Southern part of Vietnam, 
Laos and Thailand. Special selected areas, 
important from a forestry point of view, are 
photographed at 1:10,000. Photo-interpreta- 
tion and type mapping will be carried out by 
an American firm. This will result in a vegeta- 
tion map at a scale of 1:40,000, while the 
large-scale photography will be used for 
timber volume estimations. This work is to 
be started in 1960; it will possibly increase 
our information about interpretation possi- 
bilities of aerial photographs in tropical and 
sub-tropical regions. 
REFERENCES 
1. Aung Myint, U. (1958): '"The Use of Aerial Sur- 
vey in Managing Burma forests." The Burmese 
Forester, 1958, pp. 181-188. 
. Bedard, P. W. (1956): “Reconnaissance, Classi- 
fication and Mapping of Philippine Forests. 
Symposium on the Study of Tropical Vegeta- 
tion," Unesco, Ceylon 1956, p. 8. 
. Boon, D. A. (1956): Recent Development in 
Photo-interpretation of Tropical Forests. Photo- 
grammetria, 1956, pp. 382, 386. 
4. De Rosayro, R. A. (1959): “The Application of 
Aerial Photography to Stockmapping and In- 
ventories on an Ecological Basis in Rainforest in 
Ceylon.” The Empire Forestry Review, 38(2), 
pp. 141-174. 
. Hannibal, L. W. (1952): * Aerial Photo-inter- 
pretation in Indonesia." Paper presented to the 
2nd Asia-Pacific Forestry Commission of the 
FAO, 1952, pp. 1-23. 
6. Loetsch, F. (1957): A Forest Inventory in Thai- 
land. Unasylva, 11(4), pp. 174-180. 
7. Loetsch, F. (1958): “Der Einfluss des Brandro- 
dungsbaus auf das Gefüge des Tropenwaldes 
und die Wasserführung der Stróme, untersucht 
am Beispiel Nord Thailands. Zeitschrift fiir 
Erdkunde, Bnd XII, 182-205. 
8. Miller, R. G. (1957): '"The Use of Aerial Photo- 
graphs in Forestry in British Colonies." Paper 
presented to the 7th British Comm. Forestry 
Conference. Colonial Office, London, 1-7. 
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