Natural Forces LLC has introduced InvisiDye, which has been designed to complement the existing line of ReJex-it bird repellents. InvisiDye is a non-lethal avian training tool, that when mixed with Migrate, Feather Duster or other bird repellants, teaches geese and birds to avoid treated grass, plants and fruit by offering a visual warning. Treated turf looks unchanged to the human eye. Birds see a clear difference in color, giving them a visual cue to "Stay Away."