Possible Clues:

• Crop rotation affecting north of US state
• Inca crop
• Crop: one planted in network?
• Corn one stored in puzzling place
• Corn, to a Brit
• The main grain used in making bourbon whiskey
• To an American it sounds easy — I am returning sweetcorn
• Reportedly a girl’s cereal
• Johnnycake grain
• Tory Theresa's said something corny?