You may not realize that it's not the adult moths that damage a wool rug -- it's actually the larvae that hatch from the females' eggs. Since the larvae need animal-based material to eat, wool or blended wool rugs are a favorite item in which the females will lay their eggs. Moths are also drawn to the keratin in dog and cat fur. To eliminate moths that have taken up residence in a wool rug, there are several steps you can take.
Things You'll Need
Remove furniture and other items that are on the rug so the entire surface is accessible. Thoroughly vacuum the top side of the rug to remove any moth eggs and larvae that are present. Turn the rug over and vacuum the flip side. If the rug is too big to turn completely over, turn up all the edges. Vacuum at least a foot or two in from the edges. Vacuum the rug pad, if applicable, and the floor underneath as well.
Move the rug to a well-ventilated area or open the windows and doors to provide air circulation in the room in which the rug is located. Spray the rug with a moth insecticide that contains pyrethrins. Thoroughly cover the front and back of the wool rug. If possible, roll the rug up and set it aside for a day. Rolling it raises the concentration level of the insecticide. If the rug is too large, simply allow the insecticide to dry thoroughly while it's flat.
Change the vacuum cleaner bag or empty the dirt cup so the machine will have maximum suction. Vacuum the rug thoroughly on the top side and the reverse side to remove any dead moth eggs and larvae.
Read and follow the manufacturer's directions and warnings on the moth insecticide container before you use it.
Test the pesticide on an inconspicuous spot on the back side of the wool rug before you use it.