Prescribed burns also get rid of nesting places for insects and add nitrogen to the soil. Crop rotation is especially important for Central Texas corn producers, and on the Texas High Plains, as well. Populations of corn rootworms, an insect that only lays its eggs in corn fields, build up very quickly. By planting cotton or sorghum every third year, the rootworms are eliminated. Crop rotation also prevents soil diseases, or nematode buildups, for melon production and for the production of other soil-sensitive crops.
Bt cotton is an example.
Bioengineers took a gene from a bacteria that is toxic only to leaf-feeding caterpillars and put it into the plant so that the plant produces the toxin. This natural insecticide kills bollworms and budworms almost immediately. The Bt varieties should be on the market in about two years. Because resistance develops quickly, scientists are now working on ways to minimize selection for resistant caterpillars. It is important to remember that the concept behind Integrated Pest Management and biological controls is merely to lower populations to the point that insects pose no economic loss to the farmer.