Despite the interest in photographic tone, the key pictorial quality remains 
the resolution of detail. Photographic quality, in the sense of sharp image delinea- 
tion, is the most important requisite of photographs to be used for forest interpre- 
tation. The identification of species, the recognition of sites, and the measurement 
of stand size all rely in the last analysis upon object recognition. Object recogni- 
tion in turn depends upon image delineation. Although tone is an important 
pictorial quality that must be kept in mind, the chief criterion of good forestry 
photographs is picture quality (Jensen and Colwell, 1949; Spurr, 1949). 
The quest for high pictorial quality is arousing interest in better print 
materials. Aluminum foil, positive film transparencies, and other print media are 
being increasingly tried, and we may look forward to continued effort along 
this line. The problem is not how to get the requisite print quality, but how to 
get it economically in a usable form. 
COMPILA TION OF BASIC MANAGEMENT DATA 
Once the forester is provided with aerial photographs of the proper specifi- 
cations, he must begin to compile his basic management data. Included are (1) 
stand map, (2) areas of the various types and condition classes, (3) volume 
estimates, (4) merchantability estimates, (5) growth estimates, and (6) the past 
history of the tract to be managed. 
[The compilation of basic management data is affected by severe economic 
limitations. It is doubtful whether most American forest owners would be willing 
to pay more than 25 cents per acre ($ 160 per square mile) for a management 
plan, unless the forests were of unusual value. If a forester is paid $ 30 per day 
and if another $ 10 per day is required to cover overhead, photographs, and 
equipment, then the forester must prepare the management plan at a rate of a 
section one mile square every four days. Considering the variety and scope of the 
information required, aerial photographic techniques and other shortcuts must be 
used in every possible way]. 
It is not within the scope of this paper to detail inventory procedures based 
upon aerial photographs (see footnote 3; Moessner & Jensen, 1951; Haider, 1952). 
We may point out, though, that the management plan must include information 
on stand age, silvicultural condition, economic accessibility, and other factors 
not included in the typical inventory. [In the Itasca management survey, for 
example, stand age was of high importance as jack pine (Pinus banksiana) and 
aspen (Populus tremuloides) types occupy large areas. Since these species are 
short-lived, any cutting plan must pay strict attention to the age of the stands. 
In this particular management survey, therefore, as in many others, it was desira- 
ble to map out the stands on an age basis rather than on the basis of stand height 
and crown closure conventionally used in aerial survey. Although age itself cannot 
be determined directly from the photographs, it can be estimated on the basis of 
crown diameter and tree height, both of which can be measured with fair accuracy 
on the 1 : 12,000 panchromatic photographs used. The problem was further sim- 
plified by the fact that these species as well as the equally important red pine 
(Pinus resinosa) largely originated as the result of fires, and these fires could be 
mapped in readily on the aerial photographs. Forest fires have a characteristic fan- 
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