This Buzzline Birdscarer is a simple yet effective and safe means to deter  Wood  pigeons from eating your crops and other birds ...Strech the buzzline out tautly above the crop and even a gentle breeze will cause it to vibrate, giving off a sound that birds cannot tolerate. Simple to install, no running costs, harmless to birds and other wildlife, protects  fruit, vegetables, seedlings, buildings and boats. I use it myself on my brassica seed bed. 30 m