Wednesday, November 15, 2006
245-1

Soil Quality Assessment on a Northwest Missouri Organic Farming Enterprise.

John Shurts, Landmark Realty of Illinois LLC, 2280 Timber Ridge Rd., Princeton, IL 61356 and Linda Hezel, Prairie Birthday Farm, 13318 Plattsburg Rd, Kearney, MO 64060.

Organic production systems seek to produce foods of optimal nutritional quality while conserving and improving the soil resource and protecting environmental quality by using organic or natural resources without application of synthetic chemicals. Prairie Birthday Farm (PBF) is a 'micro-eco farm' established on gently sloping soils of Sharpsburg silt loam in Clay County, Missouri, which was previously under conventional corn and soybean production. In 1995 transition to organic farming began that included a primary management strategy to restore soil organic matter through organic amendments consisting of establishment of native prairie plants, composted vegetative residues, and litter from horse and laying hen operations. Assessment of soil quality - the ability to function within an ecosystem to sustain plants and animals, resist degradation (erosion), and reduce negative impacts on water and air resources – can indicate the success of management systems to optimize soil productivity and to maintain its structural and biological integrity. Our objective was to evaluate the effect of organic management on biochemical characteristics of soil (“soil quality indicators”) as an assessment of soil quality. Soils were collected at 0-10 cm depths from various plots under organic production (orchard, vegetable, pasture) and from adjacent conventional fields during 2003 – 2006 and assessed for various soil quality parameters. Soil organic matter and water-stable soil aggregates were considerably increased in all organic plots. Soil biological activity measured as dehydrogenase and glucosamidase activities were also increased, indicating improved nutrient cycling for plant nutrition and for overall soil fertility. Results of soil quality assessments suggest that organic management can successfully restore productivity of silt loam soils previously under intensive conventional agriculture and maintain environmental quality without using synthetic chemicals. The organic process practiced at PBF illustrates how resources internal to the farm (i.e., composts) can be used to restore soil productivity.