In many respects Japanese camouflage doctrine is similar to ours. Basic points emphasized
by the enemy in his camouflage work are presented below. The source is a Japanese
The introduction to the manual states that:
"The essence of camouflage lies in harmonizing it with the natural conditions of the
terrain; therefore it is most important to pay attention to shadows and colors, and
to avoid any change from the usual conditions.
"When camouflage methods are inadequate, they sometimes do more harm than good, in that
they draw the attention of the hostile forces * * *.
"Since hostile shelling, weather, and the seasons change camouflage or its immediate
surroundings, it is most important that it be repaired constantly and kept in
The manual recommends that natural camouflage material, such as weeds, vines,
trees, branches, and so forth, be used as far as possible. Artificial materials
used by the Japanese include nets, screens, canvas, and paint.
2. USE OF ARTIFICIAL MEANS
In arranging nets, the Japanese try to make them conform to the contour of the land. "When
hanging out nets," an enemy source states, "do not leave gaps where each net touches
the edges. To avoid casting shadows under nets, set up canvases under them * * *. Frames
for nets should be as low as possible. Where nets touch the ground, they must be sloped gently."
Particularly in jungle areas, the Japanese have been using nets extensively, not only for
personnel, but for weapons, installations, and horses and mules. These nets usually
have been garnished with local vegetation so as to blend well with the surroundings.
Screens are regarded by the Japanese as "simple equipment used principally for
concealment against ground reconnaissance * * *. Screens also are
used to cut off the flash of weapons at night."
In screening long stretches of terrain, installations, or equipment, the Japanese
manual warns against connecting the screens into one rigid whole. "Divide the
screening at appropriate places in order to localize damage by shell fire," the
In using paint to camouflage objects, the Japanese manual stipulates that the principal
colors should "approximate as nearly as possible the predominant colors of the
terrain. Usually the objects should be painted somewhat darker than the color of
the surrounding terrain."
The manual recommends the use of camouflage net frames over peepholes and loopholes when
the latter are not being utilized. These holes also are sometimes covered with
Periscopes and similar equipment are camouflaged to represent natural objects.
Before using wire for camouflage purposes, the Japanese recommend that it be smoked in a
straw fire to remove its shine and make it more pliable.
3. USE OF NATURAL MEANS
Natural means of camouflage must conform in size and texture to the surroundings, the
Japanese manual states, so that they will not "present a peculiar appearance" after
being arranged in place. "Before digging into the ground or covering ground with
spoil, cut away and preserve the grasses and weeds for future camouflage use."
The manual adds that grass may profitably be hung on wire as a disguise of a grass thicket.
In many instances the Japanese have camouflaged pillboxes, bunkers, dugouts, and other
similar installations with live grass, which was sown or transplanted. Several times it
has been reported that the enemy has used rice-straw bags filled with fertile dirt for
defensive covering, and has planted unhulled rice seeds, or seeds of a similar plant, on
top of the bags to secure a green growth which blended well with the surroundings.
4. USE OF DUMMIES
"Dummy installations," the Japanese manual states, "are built to present the same
external appearance as real construction, and camouflage is always applied.
"In simulating trenches, and so forth, make them look as real as possible. Their
depth must be at least 2 1/2 feet. Make the sides steep, and spread dark-colored
grasses on the bottom.
"In simulating an open-air shelter, construct it in generally the same way as a
real shelter; if necessary, imitate only the external shape, or hang out a camouflage
net and lead dummy traffic paths to it.
"Dummy covered shelters and dugouts should have such real features as loopholes,
peepholes, covering, and entrances."
1 Japanese use of camouflage on Attu, as seen by U.S. observers, was described
in Intelligence Bulletin, Vol. II, No. 2, pp. 39-43.