On our continuous wheat block we never see a slug.. but we have lost crops of wheat behind rape after many kg of pellets have been applied. The slugs proliferate in rape because the yellow flowers fall like a thick carpet in the base of the crop through the summer which is the perfect environment for breeding, egg storage, feeding, growing and re-breeding. I once knew a farmer who used to apply slug pellets on rape crops during mid-flowering to murder all the slugs before they bred under the falling flowers, he swore by this technique... we would have done it ourselves but i dont think its legal without a real and present slug risk to the crop in hand