Nematop Adult Vine Weevil Traps to control the adults. Control adult vine weevils by placing Nematop Adult Vine Weevil Traps under your plants when the adults are active i.e. between June & September. Each Nematop Adult Vine Weevil Trap consists of a specially designed wooden board, featuring grooves filled with a gel containing 2.5 million nematodes (Steinernema carpocapsae), which attracts & kills the adults. Each trap will control adult beetles in a 10sqm area or 4m of hedging & each trap is effective for approx 6 weeks. Position when adult vine weevils are active i.e. between May & September.