For years, I did my pre-season scouting in the spring of the year. It was not until recently that I found that this is not the best time. The best time to scout an area is in the winter months soon after deer season has ended.
Consider in the spring, the vegetation is new and growing. Trails that were worn by the deer are likely to be overgrown and masked by the new vegetation. In the winter, right after the deer season has ended, the trails will be fresh and well-worn making it easier to detect them and pattern the deer.
Patterning the deer right after the season has ended will give you a better sense of their movements during the season as opposed to the spring which may not represent their hunting season movements. You may be able to detect their hiding places in the winter by following their trails that would be too overgrown in the spring to follow.
In Kansas, we have an extended season that lasts until January so that means scouting in February. February is ideal because you can kill two birds with one stone. Not only will you be able to scout for the deer by finding their travel paths, but you can also shed hunt.
Shed hunting is fun and makes scouting more interesting. And, besides finding a nice trophy, you will learn something about the deer in that area. One you will know they made it through the hunting season and two, you will know the quality of the deer in the area.
Use the spring and early summer to set your stand, but do your scouting in the winter. Not only will it be more reliable, you also do not have to contend with the bugs and poison ivy.