This is a question that folks that work with rescue groups can probably help me with. I know from my past experience litter box training little kittens that they start off eating both regular clay and clumping cat litter. With my last batch of kittens I started them with Blue Buffalo pellet litter, which is made with walnut shells, then switched to clay Jonny Cat, then finally clumping litter. The current batch of newborns I'm fostering has several weeks before I have to start worrying about it, but the rescue group I'm fostering them for uses pine stove pellets for cat litter at the shelter. I'm wondering if that would be safe to use with new kittens, or if there any oils or potential hazards with using the wood pellets? I'm currently using a clumping litter for their mother, but I will need to switch to something kitten-safe once they start getting around.