AUBURN, AL--The poultry industry in the United States is big business. And the waste produced from this enormous industry--more than 16 million tons annually--creates significant environmental concerns. As environmental awareness increases, so does the challenge of what to do with all the waste. Historically, poultry manure, prized for its high nutrient content, was spread in raw form onto farm fields, but stricter regulations have placed limits on the frequency and rate of direct land applications because leached nitrates from the manure can contaminate drinking water.
In Alabama, where horticulture is the fastest growing agriculture business, researchers are looking to this green industry for answers. "With more and more landscape and nursery operations in business, the green industry could provide a new beneficial avenue of disposal for excess manure," said researcher Christopher Marble. Marble and colleagues authored a study (published in HortScience) that investigated the use of composted poultry litter as a fertilizer source for bedding plants.
The research team conducted two experiments using 'Celebrity Red' petunia and 'Quartz Scarlet' verbena planted in raised beds to simulate an urban landscape. Before planting, traditional inorganic fertilizers or composted poultry litter were incorporated into the soil; a control bed that received no fertilization was also maintained. Data was collected from plants in the center of each bed and analyzed for nutrient levels and other tests. Soil water was also tested to determine the amount of nutrient leaching.
Results showed that incorporating composted poultry litter into landscape beds as a source of fertilizer resulted in plants equal to or larger than plants conventionally fertilized. Results also showed that soil water nitrate and ammonia levels in conventionally fertilized plots were similar to plots fertilized with composted poultry litter, even when higher rates of nitrogen were applied using the poultry litter.
According to the researchers, the study proved that composted poultry litter can be used successfully as a fertilizer for annual bedding plants. They noted that while the organic waste may not be able to fully replace expensive inorganic fertilizers, it can provide an "environmentally sound supplement" and give poultry producers a new outlet for excess waste.
The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/content/46/10/1367.abstract
Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org
Application of Composted Poultry Litter as a Fertilizer for Landscape Bedding Plants
S. Christopher Marble, Jeff L. Sibley, Charles H. Gilliam, and H. Allen Torbert
HortScience 46:1367–1372. [Abstract][Full Text][PDF]