Crops that have been genetically modified for pest control through biotechnology techniques (bioengineered) were planted on approximately 16 million U.S. acres in 1997. Corn and cotton that produce a toxic protein for insect control, the B.t. toxin, were planted on 5.1 million acres. Soybean resistant to glyphosate (Roundup Ultra®) was planted on 9 million acres. In total, corn was planted on 80.2 million acres, cotton on 14.0 million acres and soybean on 70.9 million acres in 1997 in the U.S. Counting multiple treatment as multiple acres, insecticides were applied annually to 31.5 million-acres of corn and 39.5 million acres of cotton. Herbicides were applied annually to 173.7 million acres of corn, 34.9 million acres of cotton and 147.7 million acres of soybean. After seed becomes fully available, B.t. corn is predicted to be seeded on 40% of the acres and B.t. cotton on 75% of the acres. This usage of B.t. corn and cotton would result in an estimated 21.3 million fewer acres treated with insecticide annually. After seed becomes fully available, varieties bioengineered for herbicide resistance will be seeded on a predicted 47% of the corn acreage, 50% of the cotton acreage and 80% of the soybean acreage. This usage of bioengineered herbicide resistant varieties would result in changes of herbicide practices on 217.2 million acres annually. Several soybean herbicides are often used with adjuvants. Glyphosate and glufosinate usually are applied without an added adjuvant. Usage of glyphosate or glufosinate on 75% of the soybean acreage would result in 58.5 million fewer acres treated with added adjuvant annually in soybean. Bioengineered crops will have the greatest impact on corn, cotton and soybean in the U.S. but bioengineering has potential applications in all crops.