Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 2007
Publication Date: November 5, 2007
Citation: Cavigelli, M.A., Teasdale, J.R. 2007. Long-term agronomic performance of organic and conventional field crops in the mid-atlantic region [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Technical Abstract: Despite increasing interest in organic grain crop production among farmers, government agencies and other stakeholders, there is little information on expected crop yields and production challenges in organic grain production, especially in Coastal Plain soils of the mid-Atlantic region. The USDA-ARS Beltsville Farming Systems Project (FSP), a long-term cropping systems trial, was established in Maryland in 1996 to address these needs. The five FSP cropping systems include a conventional no-till corn (C)-soybean (S)-wheat (W)/S rotation, a conventional chisel-till C-S-W/S rotation, a two-year organic C-S rotation, a three-year C-S-W rotation, and a four-to-six year organic C-S-W-hay rotation. Corn and soybean yields in organic systems were, on average, 76 and 82 % of those in conventional systems. There were no consistent differences in wheat yields among systems. Weed competition alone accounted for differences between organic and conventional soybean yields, as indicated by similar estimated weed-free soybean yield among all five systems. In addition to weed competition, low N availability contributed to lower corn yields in organic than in conventional systems. Crop rotation length and complexity among organic systems had no impact on soybean and wheat yields. Corn yield, however, generally increased with increasing crop rotation length and complexity due to both lower weed competition and greater N availability in longer rotations, especially when hay was included in the rotation.