People plant their crops not knowing if the weather and the war will allow them to harvest.

BBC: (Mis)reporting Sudan's famine

Mr. Hamm doesn't think these should be called drones because farmers will use them solely for monitoring their own crops and not for military or law-enforcement purposes.

WSJ: Farmers Experiment With Drones

Farmers were frequently not paid the full world price for their crops, because governments were determined to keep local prices low in order to relieve hard-pressed consumers.

ECONOMIST: World food prices: Whatever happened to the food crisis? | The

Elsewhere, some growers who have not been able to switch crops are leaving their cornfields fallow.

ECONOMIST: The problems of plugging a square economy into a round world

High transport costs have made them uncompetitive, and their land is not well-suited to other crops.

ECONOMIST: South African farming

"Major supermarkets, in meeting consumer expectations, will often reject entire crops of perfectly edible fruit and vegetables at the farm because they do not meet exacting marketing standards for their physical characteristics, such as size and appearance, " the study said.

CNN: World wastes half its food, study finds