When New England poet Robert Frost penned, “Good fences make good neighbors,” he wasn’t thinking about trees.
But Jim and Sharon Shepherd are hoping the living fence they have created between their poultry houses and their Lawrence County neighbors will help maintain the good relationships they have always enjoyed.
The Shepherds have been on their farm 20 years, raising a beef herd while Jim also worked off the farm for Tyson Foods. Ten years ago, the couple added four poultry houses to their operation and began raising broilers for the company.
With the spike in fuel prices the past few years, the Shepherds became interested in planting a windbreak, to lessen winter heating costs for the poultry houses. According to research, a windbreak can result in a 10 to 30 percent reduction in fuel use.
Jim had visited with Skip Mourglia, a USDA Natural Resources Conservation Service Forester in Republic, Mo., about the advantages and methods of installing a windbreak. It was at a seminar in Arkansas he was introduced to what seemed an even better idea, an odor break, which involves the planting of multiple rows of shrubs and trees around the perimeter of poultry houses.
Typically, odor break trees and shrubs are placed no closer to a house than four times the diameter of the exhaust fans, with most located about 40 feet from a facility. Properly placed, the plantings block dust expelled from the houses by ventilator fans and filter out the odor constituents that cling to the dust.
“Trees can remove up to 20 to 24 percent of the constituents of odor,” Skip said. When odor travels through the trees’ needles and leaves, the odor is filtered.
When Skip received a grant to fund local research on odor breaks, Jim and Sharon’s interest in the subject made their farm an obvious place to start, and the Shepherds readily agreed to the farm becoming a test site for the five-year study. The Shepherds’ place currently is the only private farm in southwest Missouri that has an established odor break. Goals of the study include determining how effective a tree break is in controlling odor, which trees work best, the best management practices for establishing trees and which varieties will reach at least 40 percent density within five years.
With help from members of the Miller High School FFA Chapter, where the Shepherd’s son, Jay, is an instructor, the first stage of the break was planted in April 2007, after the site had been treated for weeds. Once the trees were in the ground, a weed barrier was placed and topped with mulch. The design plan included three rows, each 15 feet apart, beginning with a line of native arrowwood viburnum shrubs on the north side, nearest the houses. In designing the break, Jim and Skip chose a variety of species, with an abundance of evergreens, which have a lot of leaf surface and which, unlike deciduous trees that shed their leaves each fall, retain their needles all year.
“We want it to work 24/7,” Skip said.
The varieties they selected also are easy to obtain in the area. Some are natives, others are not, but all were chosen with their suitability to local climate and soil conditions in mind. Other criteria considered were shape and potential growth rate, as well as insect and disease resistance. A wet zone called for species that would tolerate excessive moisture. Their final plan incorporated loblolly pine and willow oak for the wet area, and Norway spruce, eastern white pine and Leyland cypress in drier areas.
The spruce and cypress have not worked well, Skip said, and the viburnum tends to be stunted in the wet. On the other hand, the loblolly pine – some are already 10 feet tall – is thriving in the wetness, and a species Ozarks farmers have long considered a pest – the eastern red cedar – is getting rave reviews.
The cedar, not available from suppliers for the April planting, was put in the ground in October 2007.
“It’s native, hardy, tenacious, easy to establish and virtually maintenance free,” Skip said. “Those cedars will grow to 12 feet. And you really can’t find a better windbreak tree for this part of the country.”
Jim didn’t have to give up his desire for a wind break to establish the odor break; his plantings serve double duty. Although planted less densely than a standard windbreak to allow air from the poultry houses to filter through the leaves, the odor break trees still provide a barrier to cold winter winds.
Until the trees are more mature, it remains to be seen if the break will make a significant impact on odor control, Skip said, but she was encouraged by a scentometer test she made last year while standing with the odor break between her and the poultry houses. The scentometer can be fitted with different sizes of orifices, through which air is pulled.
“I could tell a difference,” she said. “I had to use a larger orifice (before the odor from the houses was detectable.”
That’s good news to the Shepherds.
“The main concern to us with the odor is our neighbors,” said Jim, adding that the mature odor break also will be more aesthetically pleasing.
“When those trees grow up, they will hide these houses,” he said. “We want to be good neighbors.”
NRCS has a cost-share program through it EQIP program to help establish wind and odor breaks. For more information on the program, landowners can contact their local NRCS offices.
