Walnuts: ripe nuts should be a yellow-ish tan color, while unripe fruits will still be green. Pecan nuts are a type of hickory. Shagbark hickories tend to have smaller nuts and thicker shells. Hazelnuts are held in distinctive fringed leaves and look somewhat similar to acorns. Once dried, hazelnuts are cream colored and firm.
Walnuts and Hickories: Husked walnuts and hickories should be left to dry for 2-3 weeks, after which they can be stored, or cracked and eaten. Hazelnuts should be left to dry for 2 weeks. Shelled or unshelled hazelnuts can be kept fresh by storing them in the refrigerator for up to 6 months. Dried nuts in their shell can be kept at room temperature for 3-6 months.
Data credit 1
ISU Extension and Outreach