Herbicide-resistant weeds are becoming a more and more common problem for farmers growing grain and vegetable crops. As a result, the farmers are looking for alternatives to herbicides to control weeds. One promising approach is the use of cover crops, which are planted in the off season to protect the soil. Thick cover crop growth can often compete well with weeds during the cover crop growth period, and can prevent most germinated weed seeds from completing their life cycle and reproducing.
Large portions of the Midwest are called the Corn Belt and for good reason. Overall, about 90 million acres or 140,000 square miles of the United States are planted with corn and about half of that is in Iowa, Illinois, Nebraska and Minnesota. In most of the Corn Belt, the corn is planted in rotation with soybeans. Both are warm weather crops and the soil is left barren for nearly half of the year when the two crops are out of season.
The Netherlands is a small, densely populated country with more than 1,300 inhabitants per square mile. It lacks almost every resource one associates with large-scale agriculture. Nevertheless, it is the number two exporter of food in the world, second only to the United States, which is almost 300 times bigger. The Dutch lead the world in exporting tomatoes, potatoes and onions and produce many other crops as well.