NEB,
Here's a little explanation: The pad is dragged by a string to leave a scent trail. Deer's noses are at least 10,000 times more sensitive than yours. (or a dog's). A rutting buck can smell the estrus scent quite easily, and he will follow that scent hoping to find a estrus doe at the end of the trail. Years ago a lady that lived near us entered a stallion's corrall to feed him, not realizing that he could sense that it was her period. The Stallion attacked her, putting her in the hospital. Same with the buck. He uses his nose, to follow that trail, not his eyes. Some of the lady hunters on this site have tried this with mixed results.

Russ