Evergreens scrub out the poultry smell

Scientists looking for ways to take the “phew” out of poultry farming – at least for the farms’ neighbors – may have found an answer in trees.

Researchers from the University of Delaware have found that by ringing a farm with trees, they could cut off-site ammonia and dust emissions by more than half and odors by nearly 20 percent. So far, the best arrangement appears to consist of a border of broadleaf trees or trees with waxy leaves, enclosed within two additional rows of evergreens. The broadleaves catch the heavy particles during summer, when a farm’s exhaust fans are working hardest. The evergreens scrub the finer particles that get by the first row. In winter, when the broadleaf trees have dropped their foliage, the evergreens do all the scrubbing.

The research began in response to complaints after farms on the Delmarva Peninsula began installing more effective ventilation systems for their poultry houses. The team, led by George Malone with the university’s College of Agriculture and Natural Resources, spent six years exploring different trees and configurations. To date, roughly 35 percent of the 2,000 poultry farms on the peninsula have planted these tree-based “scrubbers,” Dr. Malone notes.

The team summarized its results Wednesday at the American Chemical Society’s annual meeting in Philadelphia.