2019 ASHS Annual Conference

The use of high tunnel systems for vegetable crop production is increasing throughout the Central United States. High tunnels offer growers environmental protection, season extension, increased crop quality and yield, and pest and disease exclusion. In contrast to greenhouse production, high tunnels are typically soil-based. Intensive cultivation and/or reduced crop rotation intervals are typical in high tunnels and can lead to compaction and degradation of soil health. The objectives of this project were to identify summer and winter cover crop species that are viable for high tunnel systems and determine their impact on belowground arthropods and other soil health parameters. High tunnel trials were conducted in 2017 and 2018. There were eight cover crop treatments planted in each season, which included grass and legume ‘Vicia villosa’ (hairy vetch) combinations as well as a bare ground control. In the overwintering season, cover crop contribution of available N (lbs./acre) to the growing system from rye ‘Secale cereal’ was 103.70 (p-value <0.01), triticale ‘Triticosecale’ and vetch 80.91(p-value <0.01), and the rye and vetch 70.17 (p-value <0.05) treatments. These treatments were significantly different from the bare control treatment. Soil characteristics including: water infiltration, soil moisture content, soil carbon, organic matter, and nitrogen were measured. Belowground arthropod abundance and trends were also monitored. At cover crop termination no belowground arthropods were found in all eight treatments (soil moisture content between 6 and 15%). Short-term changes in soil moisture resulted in changes in belowground arthropod abundance. Cover crops with high C:N ratios such as rye had higher mean abundance (11.5% more arthropods) than the average of all treatments. While there were no statistically significant treatment effects, "short–window" cover cropping resulted in changes in high tunnel soil ecology. This work is part of a collaborative multi-region OREI project that is in collaboration with the University of Minnesota and the University of Kentucky, and is also supported by a 2018 NCR-SARE Graduate Student grant.