To eat.
Iowa harvests more field corn than sweet corn.
None. The corn is grown on farms, not in the cities.
corn, soybean
corn, beans, wheat, etc.
Corn is grown abundantly in Iowa; that's where the "Tall Corn State" nickname comes from.
One half of all US corn is grown in Iowa, Illinois, Nebraska and Minnesota.
The control to this experiment is weak.
Many farmers grow corn in Illinois. The south central region below Chicago is where the most corn is grown in Illinois.
Corn, oats, and hay, though not necessarily in that order.
Much of the corn and soybeans grown in Iowa are genetically modified (GM). Very little of any of the other crops have any significant modification done to them.
The main thing that Iowa is know for growing is corn. If you visit the state of Iowa, you will see lots of corn fields.
The "Corn Belt" region in the United States is where the majority of the nation's corn is produced. It roughly covers western Indiana, Illinois, Iowa, Missouri, eastern Nebraska, and eastern Kansas, in which corn (maize) and soybeans are the dominant crops. Iowa is the largest producer of corn in the nation.