Punji stick

A punji stick is a booby-trapped stake, usually made of bamboo or wood that is sharpened and often fire-hardened, set upright in a concealed pit or along a path so that a person stepping on or into it is impaled. The English term entered use in the 1870s when the British Indian Army encountered such traps used by the Kachin people along the Burma frontier, and the sticks were frequently smeared with plant or animal poison to cause infection rather than aiming for an outright kill, forcing the enemy to spend resources evacuating and treating the wounded. Punji sticks became strongly associated with guerrilla warfare in Vietnam, where they were set in large numbers along paths and supply routes, and a 1980 amendment to the Geneva Conventions banned booby traps of this kind that remain dangerous after a conflict ends.