According to this report the tropical forest area constitutes about 45% of the 
total forest area in the world. The total removal of forest products in the tropics 
so far has been only 24% of the world total. Further, this 24% was mainly 
fuel, which was 47% of the estimated world consumption of firewood. The 
total contribution of industrial wood obtained from the tropical forests was 
only some 6% of the total world timber production. 
This extremely low output of the tropical forests can be attributed to several 
particular circumstances, as for instance: 
a. Most primary forest areas in the tropics are only to be found in very in 
accessible regions. Here the best possibility for economic exploitation of 
timber is water transport. This means that both river banks can be exploited 
to a certain extent, whereas the far remote areas remain untouched by the 
wood-cutter. Also the floating of the felled logs is mainly a question of river 
size which is further determined by such obstacles as rapids and waterfalls. 
b. The economic exploitation of most tropical forest is greatly hampered by 
the large variety in species-composition, as only a small percentage of 
this has any value for timber production. 
c. And last but not least, the amount of information needed to start a new 
lumber industry in tropical regions is still in most cases largely insufficient. 
Although the forest composition of these areas has been an important subject 
for special research for some time past, more detailed information will be re 
quired about the occurrence of valuable tree species and local topographical 
conditions in order to plan possible transportation methods. 
If we put the question: is this form of special forestry research justified, 
considering the unfavourable tropical conditions, then the answer must be, 
yes, considering the rapidly increasing demand for forest products for indus 
trial and home use. According to the information provided by FAO-officials 
we may assume that by the end of the current century the consumption of 
industrial timber will be at least twice as great as at present. It is even likely 
that this situation will be reached by 1980/1990. Taking this into consideration, 
it is clear that the tropical forests must make a greater contribution to the 
world’s timber production in the very near future. For this to be achieved 
current forest inventory methods in the tropics must be improved, and more 
complete inventories carried out where local circumstances seem favourable 
for new lumber industries. For this purpose aerial photographs have proved to 
be an excellent means of obtaining, in a relatively short time, and without much 
physical effort, general information of the existing local forest conditions. Based 
on this information it will be possible to select those parts of the forest, which 
may be more favourably exploited, according to the general appearance of the 
crown cover and topography. 
Within such selected areas a start can be made with the terrestrial survey 
necessary to obtain a more accurate estimate of the species composition and