Punji sticks would be placed in areas likely to be passed through by enemy troops. The presence of punji sticks may be
camouflaged by natural undergrowth, crops, grass, brush or similar materials. They were often incorporated into various types of traps; for example, a camouflaged pit into which a soldier might fall (it would then be a
trou de loup). Sometimes a pit would be dug with punji sticks in the sides pointing
downward at an angle. A soldier stepping into the pit would find it impossible to remove their leg without doing severe damage, and injuries might be incurred by the simple act of falling forward while one's leg is in a narrow, vertical, stake-lined pit. Such pits would require time and care to dig the soldier's leg out, immobilizing the unit longer than if the foot were simply pierced, in which case the victim could be evacuated by
stretcher or
fireman's carry if necessary. causing infection or poisoning in the victim after being pierced by the sticks, even if the injury itself was not life-threatening. Punji sticks were sometimes deployed in the preparation of an ambush. Soldiers lying in wait for the enemy to pass would deploy punji sticks in the areas where the surprised enemy might be expected to take cover, resulting in soldiers diving for cover potentially impaling themselves. ==Vietnam War==