I have an area of rocks but Truman seems to eat them from one section only so maybe I will try spraying them with the clove oil and water mixture. My gravel is not too big but Truman sounds almost like Yuna in that he eats EVERYTHING - rocks, towels, bird poop, feathers, leaves - whatever he can get his mouth on! I would like to try to curb this undesirable behavior starting with rocks! Thanks for the suggestion. Have you tried it yet? Did it work?