Pecans harvested early in the season may need drying for a couple of weeks if you plan to store them long-term. However, you can use them fresh without any special treatment. To dry the nuts, place them on screens or in mesh bags so that they get good air circulation. Place in a well-ventilated area out of direct sunlight. After a couple of weeks the nuts should be dry enough for storage. After shelling the nuts, you can freeze them to keep them fresh longer.