What crop is predominantly grown in the Great Plains?

The Great Plains is an agricultural factory of immense proportions. Between the yellow canola fields of Canada's Parkland Belt and the sheep and goat country of Texas's Edwards Plateau, more than 2,000 miles to the south, lie a succession of agricultural regions that collectively produce dozens of food and fiber products. The most important Great Plains crop is wheat. Although the United States and Canada together produce slightly less wheat than China (the world's leading wheat grower), the two North American countries account for more than half of the world's wheat exports.

Source: University of Nebraska-Lincoln