To a lesser degree these practices can reduce pine voles which live primarily underground. Just 1 or 2 fresh grains or pellets of zinc phosphide baits can quickly kill a vole that eats them, but it may take several days of feeding on anticoagulant baits to kill a vole. Zinc phosphide baits have been more effective than anticoagulant baits against meadow voles. Recent research has found that zinc phosphide is most effective when delivered as treated steam-rolled oats or as pellets. Zinc phosphide-coated cracked corn was found to be less effective.
Unwaxed bait is preferred to reduce hazard to wildlife.
Zinc phosphide loses its toxicity rather quickly if the bait becomes wet. To preserve toxicity of unused zinc phosphide baits, place the opened package within a plastic bag and seal tightly. Rodenticide baits may be attractive to domestic pets, birds and other non-target wildlife. As with all pesticides, use good judgement and take reasonable precautions to avoid problems. They are usually not effective against pine vole.