How early do you scout for bear?

I don't think you can ever start scouting too early for bear. One important thing to remember though is that after breeding has ended in June, a bear's activity will be centered around food until he dens up for the winter. This means that the areas holding concentrations of bear in the mid to late summer (when the bears are feeding on soft mast crops such as wild blueberries, blackberries, elderberry & pokeberries) are not the same areas that will produce consistent bear sightings when they switch their diet to hard mast crops (acorns, hickory & beechnuts) in the fall.

Regardless of whether you're looking for a suitable location to establish a baitsite, or an area to stillhunt or spot & stalk bears, you have to key in on where the current food sources are. Hunting a berry patch in the late fall after the berries are long gone is a waste of time, as is trying to draw bears a considerable distance away from a natural food source to visit a baitsite. The key to consistently seeing bears is to be where they're feeding, and to do that you have to continually scout to know when the bears are transitioning from one food source to another.