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Fox squirrels of the Midwestern United States scatterhoard nuts especially in anticipation of cold and snowy winters.A cacheable nut has a present value if consumed or a future value if cached.This future value declines if the nut is more perishable,more likely to be pilfered,more likely to be forgotten,or if the squirrel may not be alive to enjoy its benefits.Natural selection should permit squirrels to integrate all of these costs and benefits.But how to get the squirrel to reveal differences in the present and future value of nuts? Here we measured the squirrels giving-up densities (GUDs) on commercial hazelnuts and acorns of three species of co-occurring oaks.Nuts were buried in plastic tubs filled with gravel,thus creating diminishing returns to harvest.To measure the value of cacheable nuts,we offered hazelnuts in their shells and compared GUDs with perishable hazelnuts without their shells.The squirrels perception of the future value of hazelnuts with their shells intact was 32%higher than their present value,and this value was highest in the Fall and lowest in the Summer.Removing the shells of acorns reduced the value of highly cacheable red oaks (Q.rubra) ,had no effect on more perishable white oak (Q.alba) ,and actually reduced GUDs on the very tough to shell burr oaks (Q.macrocarpa) .Hazelnuts were always most preferred and red oak least.Patch use behavior provides a measurable projection of the squirrels preferences for food now and into the future.