National Geographic : 1970 Feb
"When this 320-acre place twenty miles from Omaha measured up, we bought." Now four miles of feed bunkers and con crete roadways to service them lace the one time grain farm. A quarter-million-dollar feed mill rolls corn into tasty flakes and mixes a molasses-flavored ration that puts 2.7 pounds of weight on a steer every day. Calves bought for fattening grow to slaughter size in as few as five months; in the 1930's cattlemen figured on two and a half years. Another revolutionary development in cattle raising unfolded for me when I traveled the hills of west Texas and the flatlands of the lower Rio Grande Valley. "Used to be you couldn't afford to have calves born between early spring and late 164 fall," a rancher told me. "Chances were that three out of four would die from screwworms getting in unhealed navels. Now that the screwworm eradication program is working, you can drop calves year round." The screwworm, I learned, is the larva of a fly that lays its eggs in open wounds of ani mals. Hatched maggots eat the living flesh; a severe infestation can kill a full-grown steer in ten days. The insect's eradication is one of the brilliant achievements of our agricultural revolution. "The female screwworm fly mates only once in her life span of three to four weeks," explained Dr. S. C. Gartman, director of the USDA's Screwworm Eradication Program facility at Mission, Texas.