From the air, snow-covered terrain is seldom entirely white, but is broken by dark areas of woods, scrub growth, and shadows made by irregularities in the ground surface, such as rock outcrops, ridges, and drainage lines.

    Concealment of tracks is a major problem in snow-covered terrain, as unconcealed tracks point the way to concealed installations. In even light snow, tracks make strong shadow lines, visible from a long distance. Sharp turns by vehicles should be avoided because ridges of snow cast heavy shadows. Whenever possible, vehicles should follow shadow-casting terrain lines, staying on the side where shadows are constant throughout the day. It is important that all vehicles keep to the same tracks. Vehicles leaving a road may achieve a short period of track concealment by driving into or away from the sun. Shadows cast by these tracks will not be apparent until the sun strikes them from an angle. Short lengths of tracks which are not too deep may be trampled down with snowshoes.

    Parked vehicles painted a solid olive drab can be concealed in snow if there are sufficient natural materials available. Park so shadow of vehicle falls on a bush or on another shadow, and break up shadow pattern of tarpaulin bows with cut foliage. If this is impossible, park facing sun or away from sun to reduce the size of the shadow cast by the vehicle. This shadow may be broken up by piles of snow, by large                                         

snow balls, or by holes dug in the snow. Snow thrown on the wheels of a parked vehicle helps to disrupt this tell-tale area.

    For vehicles which must operate in areas where snow is a daily problem, concealment is made much easier if they are painted with the snow pattern shown on page 41. Many field-expedient substitutes for paint can be used. Vehicles should be parked close to dark features of the terrain pattern. Concealment by shadows from buildings, ground formations, and trees, though effective in summer, loses much of its usefulness when snow is on the ground, as the white background lightens the shadows of those objects.

    Nets are not recommended for draping in snow. They require excessive maintenance, cannot carry a heavy snow load, become wet, bulky, and hard to handle. Garnishing becomes wet, wrinkles, and loses coverage, increasing texture and darkening tone values. They must be removed entirely during snow and sleet storms.

    Where nets are used for permanent overhead hammocks or to create permanent parking hides for vehicles, they should be garnished 100 percent. Where the terrain pattern is mottled, as during a thaw period, the perimeter areas of nets should be white; towards the center, apply patterns of slate gray, black, and olive drab. Site nets of this kind near trees, snow drifts, rocks, or other natural forms which cast shadows. Where nets are anchored directly to the ground, heap snow on the edges to relieve the irregularity of outline. All anchor stakes should be of wood. Metal stakes and driftpins conduct heat from the sun and thaw themselves free.