I used them a while back as we had a big bag of them from a guinea pig we had at the time. Was cheaper to buy one of those big bags than it was to buy just one of the tiny one's just for the guinea pigs. I did it in mid December and they sat there for a while until deer discovered them one day. Then the whole area was rooted up until they were gone. Think it's a decent addition to put out if they can find it.