This is the VOA Special English Agriculture Report.

This season, American farmers expect to plant their biggest corn crop since World War Two. Growing demand for ethanol fuel is the driving force, along with strong export sales.

Based on March estimates, the Agriculture Department expects farmers to plant thirty-six million hectares of maize. The area is fifteen percent more than last year and the largest since nineteen forty-four.

Farmers could harvest thirteen billion bushels. More than three billion of that is expected to become ethanol. Bad weather, though, delayed some planting. That could mean fewer bushels -- and even more competition between ethanol producers and other users of corn, like the food industry.

Corn prices are not as high as they were a few weeks ago. But in the past year they have gone from two dollars a bushel to almost four dollars. Growers of corn, like some other crops, also receive government subsidies.

In January, President Bush called for a big increase in the use of other fuels in place of imported oil. But some critics argue that making ethanol out of corn takes more energy than it provides. Not only that, it provides less energy than gasoline and is only adding to already high fuel costs, they say.

Critics argue that other kinds of plant-based fuels are more efficient -- for example, Brazilian ethanol made from sugar cane. But imported ethanol is taxed, while the United States ethanol industry receives tax credits.

Some agricultural specialists say increased corn production could be bad for the land. Farmers usually plant corn one year and soybeans the next. But area planted to soybeans is expected to decrease eleven percent this year.

Also, because corn gets more fertilizer than some other crops, critics say there is more risk of water pollution around farms.

Farmers in almost all states are planting more corn but Iowa is still the leader. The United States produces forty percent of the world's corn and more than half of all exported corn. Two economists recently said in Foreign Affairs magazine that the ethanol situation "is sending shock waves through the food system."

Some critics say at current rates, ethanol production could use as much as half of the American corn supply before long. But a growing fight over that supply could turn attention more to the development of other plant-based fuels.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson.