with the pine sol/mothball sock set up i never had to refresh them for the rest of the season. we DID have to make a sign at the entrance gate to explain why there were socks tied to every garbage can in the park.
it was something about the combo that is amazingly "aromatic" up close, but at 15-20 feet wasn't really noticable by people.
A Bear’s Sense of Smell
If someone were to ask you, "how does a bear smell," you could answer in two ways. Bears smell real bad – or so I'm told – or bears smell exceptionally well, as I discuss below.
Bears are thought to have the best sense of smell of any animal on earth. For example, the average dog's sense of smell is 100 times better than a humans. A blood hound's is 300 times better. A bear's sense of smell is 7 times better than a blood hound's or 2,100 times better than a human.