1. Advanced agricultural technology: The United States leads the world in agricultural technology, especially corn planting. With its own mechanized industrial production, agricultural production has entered a new stage.

2. Superior geographical conditions: The United States has a flat and open terrain, a mild climate, fertile soil and abundant precipitation. In addition, the land is vast and sparsely populated, and the transportation is convenient. It is not only suitable for planting corn, but also convenient for sending corn to other places after planting. These geographical conditions provide a good foundation for high yield of maize.

3. Corn, named Zea mays, is an annual herbaceous crop of Gramineae. It is a root crop, and its underground root is the main part of the root system, which is buried deeply. The stem consists of nodes, which are cylindrical and have hard tissues. The leaves of corn are composed of leaves and leaf sheaths.