We have used horse litter for at least 8 years or more. It is pine and I have had no problem except one of our foster moms was allergic to the pellets (not the ferrets this time but the pellets). They are about the same as what you can get pkg'd at the pet stores with a cute little ferret on the front 10 lbs for around $12 where the horse pellets are 40 lbs for around $7 and we sell it for $10 to cover cost of going and getting it and stocking it. One bag can last an average household about 6 plus months. You put very little into the pan since ferrets don't bury "it", it slurps up the liquid and nullifies the ammonia. I don't use it for the horses because I don't want any confusion I am using the ferret litter so I use flakes for them but I am told if I use the pellets with them, I would never use the flakes again. I highly recommend it - now about the only side effect is when it does get wet, it does dissolve into a powder and can be tracked out of the pan - that isn't as bad as cat litter. If you like, you can use it in flower beds afterward but you need to add some nutrients to it to make a good mulch or soil breaker up (like in clay to make it more dirt consistency). Millie and her Danes at the Texas Ferret Lovers Rescue www.txferretrescue.org [Posted in FML 7403]