COMMISSION VII: INTERPRETATION OF VEGETATION 
The equipment used for this interpretation 
was an ordinary pocket stereoscope; for the 
delineation of types the normal mirror stereo- 
scope is the most practical. The annotated 
vegetation boundaries were afterwards trans- 
ferred to available topographic maps, by 
Zeiss Sketchmaster. Mapping scale was 
1:40,000. An occasional check afterwards 
made in the terrain showed that the vegeta- 
tion boundaries mapped were in accordance 
with the situation in the field. 
PHILIPPINES 
According to information obtained from 
the Forestry service in this country, the fol- 
lowing can be recorded. The majority of the 
aerial photographs available were made by 
the U. S. Army during the last war. These 
photographs cover most of the principal is- 
lands of the Archipelago. Further photogra- 
phy was carried out after the war until 1953, 
by the USA. 
scales varying between 1/40 to 1/45 thou- 
sand. 6" cameras were used with panchro- 
Photographs were made on 
matic films. Prints were made on glossy paper. 
Very recently the Philippine Air Corps ac- 
quired the necessary training and facilities to 
take aerial photographs. 
There seems to be an increasing demand 
for aerial photography to satisfy the particu- 
lar requirements of forestry. Aerial photogra- 
phy on a larger scale is specially desirable to 
overcome troubles in forest type mapping and 
volume estimation. Although there is a lack 
of technically trained personnel, some work by 
the Bureau of Forestry has been done. 
This work is focused particularly on type 
delineation and mapping. The mapping work 
includes preparing photo mosaics and the 
Vegetation 
types are delineated on the photographs and 
compilation of contour maps. 
are transferred to a base map. The practical 
application of this phase of the work is limited 
to a broad presentation of topographical fea- 
tures and general forest conditions. Because of 
to collect better and more de- 
urgent need 
tailed data in order to work towards a sus- 
tained yield, it is believed that the use of 
aerial photography to speed up the inventory 
work is almost indispensable. 
SAN SALVADOR 
Aerial photographs were used to obtain 
better information on prevailing forest condi 
tions in some mountainous regions. Based on 
the interpretation the following information 
can be given for the Metapán region covering 
an area of approximately 100 sq. km. The 
following 3 belts based on elevation above sea 
level, are indicated: 
From 800 to 1,200 m., mainly covered by 
open Pine forest with some clearings, total 
area 5,000 ha.; 
From 1,200 to 1,500: mainly covered 
pastures and occasional shrubs and 
lated Pine groups. This elevation belt is 
further characterized by steep incised gul- 
leys caused by violent erosion activity. 
Total area about 8,000 ha. 
From 1,500 to 2,500: a vegetation of Mossry 
Forest with a rather dense crown canopy 
with 
1S0- 
and a large variety in species composition. 
Total area about 1,350 ha. 
This information could be used as a base 
for a more intensive mapping project in the 
future, in order to plan a more effective forest 
protection in combination with better erosion 
control, and to improve timber exploitation 
in the Pine Forest belt. 
SUDAN 
In 1958/59 forest inventory work was car- 
red out in the southern provinces of El 
Ghazal and Euatoria, and aerial photographs 
taken with a Williamson Eagle I X and a Wild 
RC 8 (with Aviogon lens) at scales of 
1:16,000 and 1:40,000 were used for forestry 
interpretation. The photographs were taken 
at the normal combination of panchromatic 
films through minus blue (i.e. yellow) filters; 
however, experiments were started with in- 
frared photography. 205 sample plots were 
measured and forest type maps prepared for 
an area of abt. 4,000 sq. miles at 1:100,000 
scale and nearly 20,000 sq. miles at a scale of 
250,000. 
A reconnaissance aerial survey was carried 
out with a De Havilland ‘‘Dove’’ on 14,000 
sq. miles of the Dom palm (Hyphaenea 
thebiaca) forests in Kassala province in east- 
ern Sudan using 1:250,000 scale maps. A few 
sample plots were enumerated along the river 
Atbara and in the Dom forests of the Gash 
river. À map was prepared at 1:250,000 scale 
giving the location of the Dom stands divided 
into density and width classes, and the Dom 
nut production estimated. 
SYRIA 
Forest inventory work based on aerial 
photographs has been carried out in the 
period 1956/57. This was executed as a part 
of the Technical Assistance Programme for 
this country under supervision of UNO. The 
total forest area to be surveyed was 5,000 sq. 
km. situated in. N.W. Syria. Aerial photogra- 
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