Scientists say just three rows of trees around chicken houses can reduce dust, ammonia and smells. Transcript of radio broadcast:
the VOA Special English Agriculture Report.
trees around poultry farms can improve air and water quality -- and please the
noses of neighbors.
Scientists have shown that just three rows of trees near
poultry houses can reduce the release of dust and ammonia. Trees can also
reduce the strong odor of ammonia gas.
trees capture dust, ammonia and odors in their leaves. They can also reduce
energy use. They provide shade from the sun, reducing cooling costs in summer.
And they act as a windbreak, reducing heating costs in winter.
Scientists say the trees can also
improve water quality around farms by removing pollutants from soil and
years ago, in the eastern United States, people were objecting to the odor of
poultry farms on the Delmarva Peninsula. Delmarva is where the states of
Delaware, Maryland and Virginia come together. Each of the two thousand farms
there can house an average of seventy-five thousand chickens.
the farms used windows to provide fresh air in the chicken houses. Farmers
rarely planted trees or tall crops around the buildings, so there would be no
barrier to the airflow.
But then farms began to use new
ventilation systems. Instead of windows, the new systems used tunnel fans to
circulate air. The fans directed airflow from the poultry houses toward the
homes of neighbors.
A team led by George Malone at the
University of Delaware began dealing with the problem in the year two thousand.
The team recently presented a report at the national meeting of the American
Chemical Society in Washington, D.C.
Over a period of six years, the
scientists found that planting three rows of trees reduced total dust and
ammonia by more than half. And they say the trees reduced odors by eighteen
For the first row nearest the fans, they
generally suggest using trees that lose their leaves in the fall or trees with
waxy leaf surfaces. They suggest evergreen trees for the other two rows. Some
trees work better than others. And what works in one area of the country may
not work as well in other places.
may think trees will take too long to grow to be effective. But some trees can
grow as fast as three meters a year.
Today, one-third of the Delmarva farms
have planted trees, technically known as vegetative environmental buffers.
These buffers can offer a way to cut pollution, save money and make the
that's the VOA Special English Agriculture Report, written by Jerilyn Watson.
I'm Jim Tedder.