|KREMER, ROBERT - University Of Missouri|
|HEZEL, LINDA - Farmer|
Submitted to: eOrganic
Publication Type: Trade Journal
Publication Acceptance Date: 7/31/2015
Publication Date: 11/1/2015
Citation: Kremer, R.J., Hezel, L.F., Veum, K.S. 2015. Soil health improvement in an organic orchard production system in Northwest Missouri. Proceedings of the Organic Agriculture Research Symposium, February 25-26, 2015, LaCrosse, Wisconsin. eOrganic. Available: http://eorganic.info/oars2015.
Technical Abstract: Prairie Birthday Farm (PBF), a diversified, organic enterprise on the loess hill landscape in northwestern Missouri, was previously managed as a conventional corn-soybean production system. Transition to organic farming began in 1995 and included soil organic matter restoration with native prairie establishment and organic amendments. Assessment of soil health was initiated in 2003 to monitor organic management impacts on soil productivity. The purpose of the PBF orchard study was to evaluate ecologically-based practices of integrating native plants and organic amendments into the orchard on biological indicators of soil health. Ecologically-based management restored and improved soil health on degraded landscapes. Soil organic C (SOC) gradually increased by 25% to greater than 60 g kg-1 over six years compared with relatively stable SOC contents of about 30 g kg-1 during the same period at control sites. Soil aggregate stability increased by 70% in orchard alleys, reflecting contributions of established root systems of native vegetation and high SOC. Soil enzyme activities increased by at least 30% in alley and organically-amended sites, demonstrating substrate contributions from vigorous roots and systematic amendments with organic materials that enhanced soil microbial activity. Microbial community structure and biomass determined by phospholipid fatty acid analysis was similar in compost-amended soils and alley sites under either native vegetation or tall fescue (non-treated orchard). Microbial diversity improved slightly, however, improved functional diversity (soil enzyme activity, aggregate stability) suggests that microbial assemblages within organically managed soils were more effective in mediating biological processes to achieve improved soil health than in non-organically managed sites.