THE MILITARY PROBLEM OF VEGETATION AND TERRAIN
ANALYSIS BY AIRPHOTO INTERPRETATION
Page E. Truesdell.
The effect of vegetation and terrain on military operations has been a
problem confronting military commanders throughout history. Numerous
examples could be cited wherein favorable or unfavorable terrain conditions
have been a major factor in a military operation. In many instances the amount
and type of vegetation and the lay of the land have been of primary importance
in the outcome. This is true regardless of whether the operation was conducted
by armies, or where naval units were pitted against land mannoevres. Both the
attacking and the defending forces must be cognizant of the terrain conditions.
Such is the case not only during historical times but also in the modern age.
Even today with the advent of modern equipment there are several important
aspects in which the military commander has need for detailed and accurate
information concerning any area of contemplated military operation.
In the past the terrain condition was usually obtained by consulting avail-
able maps and charts of varying accuracy. This information was often supple-
mented by personal accounts of the area as noted by advanced military parties
or scouts. Even the earlier settlers and Indians of the United States whenever
possible took advantage of the vegetation and terrain during periods of conflict.
Points of highest elevations were used as a means for determining the lay of the
land. With the advent of aviation and the resulting surge of aerial photography
the high vantage point for studying the terrain became a major factor. As the years
passed aerial photographs won their place in military intelligence. First aerial
photography was only regarded as a means of obtaining general information,
later as a source for accurate mapping and finally as a means of evaluating
many phases of a military operation. Not the least of these is the estimation of
terrain conditions as shown by the presence or absence of vegetation and recog-
nizable landforms.
As is generally the case in all new sciences, the interpretation of aerial
photos has progressed rapidly. Not long ago we had the general or all around
photo interpreter. However as the fund of information contained in aerial pho-
tography has been exploited and effectively used, the need for specialists in this
highly important field of intelligence has become necessary. The need for an all
around photo interpreter will probably never leave us, but in certain instances
he must give way to the specialist who, as in the medical and other professions,
takes over in cases of emergencies or for special needs. These specialists, be they
photogeologists, botanists, pedologists etc. have their special niche in the evalua-
tion of terrain conditions from aerial photography.
Unfortunately, today there are not enough of these technical specialists to
meet the demand. As a result the general photo interpreter must be ready to do
the work of the specialist when the need arises.
In modern warfare, vegetation and terrain conditions may have several
effects, such as:
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