I've lost the link, but you came to mind for another similar dealie recently. apparently pine nuts were a HUGE Native American cash crop when the Pioneers were invading ... and prior to European arrival, a key food crop. But the weird part, or at least the part that makes it not annually reliable is that various pine trees only put out nuts every 3 or 7 years (I think depending on the species of pine) ..

just wanted to share!