National Geographic : 1993 Jun
The nutrient-rich runoff, washing down stream to the bay, has fueled mammoth increases in the growth offloating algae, deny ing vital sunlight to underwater plants. These aquatic plants, on which ducks, geese, and swans feed and in which crabs hide to shed their shells, have been wiped out across tens of thousands of acres. Additional damage comes when the algae die and decompose, using up oxygen from the water needed by the bay's other aquatic life. "We do have a problem," says Sherman Haas, who raises cattle, hogs, grain, and hay in a valley that rolls between Nittany and Brush Mountains in central Pennsylvania. "But you wonder if your farm can be hurting Chesapeake Bay as bad as some say." No single farm is - nor is agriculture the sole source of the bay's problems; but farmers, though they number less than 3 percent of the bay region's people, work a quarter of the 41 million acres in the watershed. They apply nearly 700 million pounds of commercial fer tilizer annually. And today's farms also have far greater concentrations of livestock and poultry-and their manure-than they did 50 years ago. Haas became a farmer in 1983, moving near the Centre County village of Rebersburg to get away from growing development around the city of York. It's easy to understand why, seated on the porch in the cool shade of his old stone farmhouse. The valley shimmers green golden in the late summer heat. The corn is tas seling gold-to-brown, and a playful breeze blends barnyard odors with scents of alfalfa curing sweetly in the hayfields. It is difficult to reconcile such beauty and fullness of the earth with water-quality problems happening more than a hundred miles away. In an effort not to add to the bay's troubles, Haas is trying to send out no more nutrients than he takes in. For that reason, he weighs every pig, every bag of feed and fertilizer, every truckload of hay, livestock bedding, and manure leaving and entering his operation. He works closely with Les Lanyon, a Pennsylva nia State agronomy professor. "We have changed the world," Lanyon told me, referring to the vast increase in THOUSANDS OF TONS ofPennsylvania manure and millions of gallons ofWashington, D. C., area sewage head toward the bay each day. The straw this Amish farmer spreads with manure (upper left) acts to slow nitrogen release; a proposed state law would require management plans for fertilizer and manure on large farms. The Blue Plains plant intercepts sewage before it reaches the Potomac River, producing compost (below) sold for soil conditioner.