Iowa has over 68 farms producing chestnuts on over 300 acres.
Ripened chestnuts (with a split open burr) should be harvested immediately. Chestnuts should have shiny, glossy, firm shells with no cracks or holes. It should feel heavy for its size
Chestnuts should be refrigerated in a mesh, perforated plastic, or paper bag. Unshelled nuts will keep up to 3 weeks. Shelled chestnuts should be refrigerated and used within 3-4 days. Chestnuts can be frozen for up to 6 months
Data credit 1
ISU Extension and Outreach