The RESCUE!® W·H·Y® Trap can be used outdoors wherever there is a paper wasp, hornet or yellowjacket problem. We recommend the trap be placed at least 20 feet away from an outdoor activity area, such as a patio or deck. Generally speaking, the W·H·Y® Trap will capture more paper wasps near a house structure, and more hornets and yellowjackets near a natural setting of bushes and trees. It can be highly effective to place multiple traps around the perimeter of a yard or area where insects are entering. The trap should also be placed at least 20 feet away from a known yellowjacket nest.