1. GENERAL

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 Army manual.¹

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 good condition."

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

a. Nets

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.

b. Screens

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 manual states.

c. Paint

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."

d. Miscellaneous

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 grass.

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."