A Cooperative Nutrient Management Project in the
Upper Shoal Creek Watershed of Southwest Missouri

Adam Reed
Nutrient Management Conservationist, USDA-NRCS
Cassville, MO 65625

Dan Philbrick
Resource Conservationist, USDA-NRCS
Cassville, MO 65625

Rita Mueller
RC&D Coordinator, USDA-NRCS
Republic, MO 65738

Introduction

Southwest Missouri has an abundance of clear streams, springs, and lakes. However, a rapidly expanding poultry industry and its associated waste has created serious water quality concerns. The poultry industry is one of the area's largest employers, contributing heavily to the state and local economies. In 1996, the value of Missouri poultry production surpassed beef for the first time (NASS, 1997). Southwest Missouri's annual poultry production is about 190 million broilers and 20 million turkeys. This production generates approximately 475,000 tons of litter per year. The most common method of litter disposal is land application. With increased poultry production in Southwest Missouri, there will be increased competition for land on which to spread poultry litter.

In Southwest Missouri, the challenge is how to utilize the poultry litter as a fertilizer resource, while maintaining high water quality. The Southwest Missouri Resource Conservation & Development (RC&D) Council addressed this challenge by proposing a five-year project in the Upper Shoal Creek Watershed. This watershed is approximately 92,000 acres, with land use estimated to be 73 percent grassland, 20 percent forest land, 5 percent other (water, roads, farmsteads), and 2 percent cropland.

This project was designed to demonstrate that with good nutrient management, poultry production and high water quality can coexist. The Upper Shoal Creek Watershed was chosen as the project area for a number of reasons. The watershed has a high concentration of poultry farms and several large integrator companies are represented. Fortunately, this watershed has no urban influences such as urban storm runoff or municipal waste discharge.

This project will address five primary objectives as shown below.

1. Develop good working relationships with the poultry industry and independent farmers.
2. Monitor soils receiving poultry litter.
3. Determine nutrient concentrations of poultry litter.
4. Monitor streams and springs for nutrient content.
5. Educate poultry farmers and the public about the findings of this project.

The development of good working relationships with the poultry industry and independent farmers was essential for the success of this project. Ten demonstration poultry farms were identified for close monitoring of soil and poultry litter. These farms were selected by allowing the poultry industry to hand pick the demonstration farms. This method of selection helped develop trust from the poultry farmers and involved the poultry industry with the project.

Soil sampling is performed by transecting each field and making a composite soil sample from 10-15 individual soil cores. Soil samples are taken to a 6" depth and sent to the University of Arkansas Soil Diagnostic Laboratory in Fayetteville, Arkansas. Samples are analyzed for pH, nitrate-nitrogen (NO₃-N), phosphorus (P), potassium (K), and calcium (Ca). Poultry litter applications are traditionally applied to meet the N needs of the crop, which rapidly builds soil test P (STP). Thus, STP is this project's primary soil quality concern. The STP is extracted by the Mehlich III procedure. Annual soil samples will monitor STP increases following poultry litter applications.

Poultry litter samples are taken and analyzed for N, total P (TP), and total K (TK). The University of Arkansas is performing all litter testing. Due to the variability of poultry litter within an individual poultry house, the litter samples are collected as described by Vandepopuliere et al. (1992). Poultry litter production and the placement of litter are also recorded at the end-of-year clean out.

Results from soil and litter testing are used to determine poultry litter application rates, or if poultry litter is the best fertility choice.

Ten surface water sites (6 streams and 4 springs) are monitored for nutrient concentrations. Grab samples are taken monthly and sent to Q.W.A.L. Laboratories in Pittsburg, Kansas for nutrient analysis. Water samples are analyzed for NO₃-N, TP, and TK. Methods for analysis are EPA-353.1, EPA-365.4, and EPA-200.7, respectively

Information gained through this project will be presented to any and all interested parties. Public meetings, poultry grower meetings, and field days will also be used to disseminate information. This project is publishing a quarterly newsletter, which is currently being sent to over 500 poultry producers in Southwest Missouri. A minimum of three informational guide sheets will also be published by the University of Missouri Extension Service.

This project has been received by the poultry industry and the independent farmers in a very positive manner. Environmental groups of Southwest Missouri, which often blame poultry for polluting the water, have also been positive toward this project. Ten demonstration farms have been identified. Some of these farms needed to make improvements concerning litter management. They all now have waste management systems that meet their needs while minimizing the likelihood of nutrients being lost to surface and groundwater. These positive results with the ten demonstration farms have reached many others by word of mouth. This has allowed us to work with far more than just ten poultry farms.

Soil samples taken in 1997 within the watershed represented over 3,300 acres. The majority of these fields had a history of poultry litter applications. The acre-weighted STP was 220 pounds per acre. However, there were several fields with STP less than 10 lbs/ac and a few greater than 1,000 pounds per acre. The native STP for this part of Missouri is approximately 10 pounds per acre. Poultry litter has greatly improved grass production on local soils; however, water quality concerns about excessive STP impacting runoff water quality are coming to the forefront. This project will start recommending litter application rates based on a combination of the N needs of the crop and STP levels in the soil.

Poultry litter tests have shown that what was once considered waste is truly a valuable fertilizer resource, as shown in Table 1. Poultry litter in Southwest Missouri is generally sold for $10.00 per ton. However, if one purchased the same nutrient equivalent as commercial fertilizer it would cost over $38.00, which does not take into consideration micronutrients or the benefits of organic matter additions. This economic comparison has been an effective tool for convincing poultry producers to use their litter as an economic resource. By knowing the nutrient value of this resource, farmers are realizing that they can afford to haul it some distance. In the past, many farms spread litter heavily on fields in close proximity to the poultry houses. This is one reason for the excessively high STP levels in some fields. Hauling of litter will probably become more prevalent as STP levels increase in local fields.

This project cannot identify the source of stream nutrients, which include poultry litter, commercial fertilizer, livestock, and failing septic systems. However, stream monitoring has shown water quality to be typical of a highly agricultural grassland region. Figures 1 and 2 show two typical monitoring sites in the Shoal Creek Watershed. Nitrate-N concentrations in the streams and springs generally range from 2-4 ppm. This is well below the 10 ppm EPA drinking water standard, which is important because Shoal Creek is a drinking water supply for over 60,000 people (intakes located below project area). Total K from monitoring sites is generally below 2 ppm. Total P in the water has always been below our detection limits of 0.1 ppm. Efforts are being made to lower the detection limits. This is important because very low concentrations of P in the water can result in eutrophic conditions.

Conclusions are not possible at this time; however, we have learned a great deal from the first year of this project. Early findings have shown:

1. A willingness from farmers to cooperate with water quality projects,
2. Soil testing has confirmed that poultry litter does increase STP levels,
3. Poultry litter is more valuable than many people realized,
4. Water quality does not show any impairment due to excessive nutrients.

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