Here, farmers engage in the labor with pride and professionalism.

The families of Jay and Bob Lynch between them own some 1,800 acres of farmland in Humbolt County, about two hours' drive north of Iowa capital Des Moines. Like most farms in the area, the Lynch farm grows mainly soybean and corn.

"Many people thought we still led the life of old generation farmers. They are surprised to see we use BlackBerry smart phones to follow weather changes and computers to exchange information with other farmers on the Internet," Jay said.

Jay often takes visitors to his tractor and gives them a ride. "There is a GPS here in the cab, so the tractor could drive by itself at a press of button, tilling the land and applying fertilizer."

Jay is not just a farmer minding his own business. He is actively involved with the Iowa Corn Growers Association, chairing the Animal Agriculture and Environment Committee of the association, and serves as a voting delegate for the U.S. Grains Council and the National Corn Growers Association.

Iowa, with 71,665 miles (115,334 km) of streams and rivers and more than 161,000 acres of lakes, ponds and wetlands, is rich in water resources. Farmers here are concerned with water quality and are implementing new technologies and production practices to improve water quality throughout the state.

Over the past several decades, conservation practices, including soil testing, nutrient management planning, tillage and crop residue management, crop rotation and precision agriculture techniques, have helped farmers reduce erosion, runoff and sedimentation. Iowa's erosion rate has fallen 33 percent since 1987.

A recent study estimated Iowans invested about 345 million U.S. dollars annually in conservation practices. Farmers here have voluntarily restored more than 250,000 acres of wetlands.

Farmers in Iowa are highly educated, as most have agriculture degrees. Through their corn checkoff (a system in which a proportion of crop proceeds are pooled for use in improving the sector), they have invested several million dollars in research into efficient nitrogen use.

Over the past eight years, checkoff-funded bio-tech scientists have been trying to insert a gene into the corn plant that will require at least 20 percent less nitrogen per bushel, meaning more productivity with less environmental impact.

Jay said proudly that "the choices I make on my farm are to improve the environment for today and the future."

More than half the soybeans produced in Iowa are for export and China is a major buyer. The Iowa Soybean Association organizes crop tours for people from China, and has trade tours to China every year, allowing farmers to meet their customers.

According to the U.S. Department of Agriculture, China became the top market for U.S. agricultural goods last year, purchasing 20 billion dollars' worth of U.S. agricultural exports, which supported more than 160,000 American jobs.

Iowa State Governor Terry Branstad has offered biotechnology, advanced manufacturing, food processing, and financial services, in which Iowa is a world leader, to build a future partnership with China.