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of vegetation and other objects of nature, the number of orienting points 
reflected on the multispectral aerial photographs increases compared, with 
panchromatic aerial photographs by 2 times in forests that have been, in 
utilization, but by 3-4 times in a virgin forest. Among the total number of 
forest compartments detected on panchromatic aerial photographs, 50-75 per 
cent require precise placement of boundaries by visual examination, while 
with false color multispectral photographs only 10-20 percent need the 
verification of such kind. The degree of ease of detection of boundaries 
of forest compartments on false color multispectral aerial photographs is 
less dependent upon the scale compared to panchromatic photographs and thus 
permits the use of aerial photographs with smaller scales for accurate 
surveying work [6]. As well as the division of the forest stock into forest 
compartments, aerial photographs are used in forest inventory for direct 
forest estimation. 
It was based on the rational combination of interpretation of 
false color multispectral aerial photographs with the scale 1:15000 with 
ground forest estimation [ 4 ]. 
The interpretation based on the new technology is carried out 
by the method of analyses and measurements that provide the intensive 
investigation of the object, the development of measuring interpretation, and 
correlation between interpretation indices and estimation ones. The study 
and maintenance of mutual bounds between the interpretation indices, reflected 
on the aerial photos and estimation indices is carried out in the homogeneous 
woody vegetation type areas. For the purpose special test sites are used and 
data of selected measuring-innumerative estimation in the most typical forest 
compartments are made. Measuring data in the test sites and typical forest 
compartments provide the following relations: between diameters of crowns and 
diameters at breast height; between heights and diameters at breat height; 
between heights of trees and heights to the maximum breadth of their crowns; 
between heights and diameters of crowns, heights of trees and heights to the 
ends of crowns, between crown-density and crown stock; between the number of 
visible and invisible trees on aerial photos: and there also exist many inter 
relationships between diameters of crowns, age and the stock, height and 
overhead cover density. 
The stereoscopic analysis of aerial photos for the measurement 
of difference in absolute parallax and for some other measurements, various 
stereoscopes and other stereo instruments are used as well as a measuring 
lens and other devices. 
With the aid of the method of analysis and measuring (or just 
measuring) the composition, the density (crown density) is determined at the 
laboratory on the base of aerial photos. Due to the difference in absolute 
parallax, the height is determined; on the basis of correlations in the 
composition, density, height and diameter of crowns, the diameters of trees 
and the growing stock are calculated. The ecological conditions are 
determined on the basis of indirect indices: in accordance with certain forms 
of relief, tone and color of imagery, the structure of overhead cover and so 
on. Non-vegetated areas (deforestation, moors, fields) are interpreted on