REPORT OF COMMISSION VII 
G VI1-41 
Problem area V Denuded lands with insufficient soil material to support 
forest cover. Such lands include landslides, alluvial fan 
at river bottoms where swift flood water deposits boulders, 
gravels or coarse sand. Only by excessively expensive 
measures can such lands be made productive. 
The soil and water conservation problem areas were determined by the 
combination of (1) slope, (2) degree of erosion, and (3) combined rating of soil 
depth and texture. A combination guide was used to help the interpreters to 
determine problem areas. 
An intensive forest survey was started in August 1955 for the management 
plan of the Experimental Forest, National Taiwan University which uses 
1:12,000 scale infrared photos. The area is approximately 34,000 ha. The 
minimum mapping area is 3 ha. on the 1/20,000 scale forest type and stand 
size map. In addition to the forest types for the over-all survey, the following 
forest types are added: 
Common name Scientific name 
Chinese fir Cunninghamia lanceolata 
Japanese fir Cryptomeria japonica 
Bamboo-hardwood mixture 
Bamboo stands are separated as follows: 
Map Symbol 
B1 
Bm 
Be 
Scientific name 
Sinocalmus latiflorus 
Phyllostachys makinoi 
Phyllostachys edulis 
In nonforest cover type delineation, banana is recognized and added. 
Abitibi Power and Paper Company of Canada has completed the forest 
inventory of all of its holdings, using 1:15,840 summer panchromatic photog 
raphy. This required four years with a staff varying between 30 to 45 men. Six 
areas of forest were involved, varying in size from 1,090,000 acres to 6,400,000 
acres. Sample areas amounting to less than 1 per cent of the total were studied 
on the ground to provide basic stand volume table data; utilizing experience in 
interpretation of the men involved. The remainder was interpreted in the 
office. Maps showing the species, composition, age, and volume of merchantable 
timber in cunits per acre were prepared, along with detailed estimates by species 
for each type area. The accuracy required and achieved was ±10 per cent by 
volume with a probability of 0.95 that the error did not exceed this in any 100 
square mile unit. 
Also detailed photo interpretation on 1:15,840 summer panchromatic 
photography was studied for detailed surveys for logging purposes. The accuracy 
required is ± 10 per cent at the 0.95 probability level for areas of 5 square 
miles. To obtain this accuracy with these photographs, ground samples were 
taken in every merchantable forest type interpreted. Each of the six Divisions 
of the Company using this method averaged approximately 25 square miles a 
year. 
Instruments used consisted of lens type stereoscopes, parallax wedges, 
multiscope, and wedge scales. Photo techniques required identification of tree 
species, measurement of tree heights and stand densities. 
The nationwide Forest Survey program of the U. S. Forest Service uses 
aerial photos intensively. Photos are used to interpret forest areas, forest sites, 
stand size and condition, and forest types. Complex sampling schemes are used