Previous studies suggest that producers tend to store crops longer than makes economic sense. Since decisions to sell are irreversible, there can be a real option value from waiting to sell grain. This real option value may explain why producers appear to store too long. A seasonal mean reversion model is estimated that allows prices to be a random walk within a season, but mean reverting across crop years. Unless prices are extremely low, it is optimal for producers to sell before the mean reversion begins. Thus, the real option value of waiting cannot explain why producers seem to store at a loss in the latter part of crop years.