I have always wondered about the earth scents. Smell receptors become desensitized to constant odors. Have you ever walked into some ones house and sensed a distinct smell, yet the owners smell nothing. It is because they no longer register that odor.

If earth scents in fact replicate the natural odor of the woods I would think they are un-perceivable to the deer. If this isn’t true, deer would be constantly bombarded with natural earth cover scent, that would impair there every day ability to detect foreign odors.

I have the same doubts about pine and oak scents.

All in all I agree with most that keep clean and no cover scent is best.
When I do use a cover I like fox urine.