Impacts of winter grazing on soil health in southeastern cropping systems

Authors: CROWELL, HAYLEY - Auburn University; GAMBLE, AUDREY - Auburn University; FENG, YUCHENG - Auburn University; PRASAD, RISHI - Auburn University; Balkcom, Kipling

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/11/2020
Publication Date: 12/15/2020
Citation: Crowell, H., Gamble, A.V., Feng, Y., Prasad, R., Balkcom, K.S. 2020. Impacts of winter grazing on soil health in southeastern cropping systems [abstract]. ASA-CSSA-SSSA International Meeting.

Interpretive Summary:

Technical Abstract: Soils in the Coastal Plain are often degraded and characterized by low organic carbon as a result of historically intense row cropping. A rotation of cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) under conventional tillage is typical in this region, but an opportunity to encourage diversification of rotations that improve soil quality exists. If managed properly, combining annual winter grazing of cover crops in a cotton-peanut (CP) rotation under conservation tillage may provide additional soil organic matter to improve soil health and fertility. Studies are needed to establish guidelines for integrated livestock systems (ICL) which maximize soil health benefits while maintaining yield and providing quality forage for livestock. Using multiple soil health indicators, such as total carbon (TC), permanganate oxidizable carbon (POXC), microbial biomass-carbon (MBC), arbuscular mycorrhizal fungi (AMF) colonization rates, water stable aggregates (WSA) and soil penetration resistance (PR), a quality evaluation of the impact different lengths of winter grazing have on soil health can be completed. A study was established in 2018 at the Wiregrass Research and Extension Center in Headland, AL to determine the effects of an ICL in which winter grazing livestock were incorporated into a CP rotation with a winter cover crop mixture of ‘Cosaque’ oats, ‘FL401’ rye, ‘Sunrise’ crimson clover, and ‘T-raptor’ brassica hybrid. Three treatments of cattle removal dates (i.e., mid-February, mid-March, mid-April) and an ungrazed control were compared to assess the effect of grazing period length on TC, POXC, MBC, AMF colonization rates, WSA, and PR. Significant differences in soil health indicators were not detected between cattle removal treatments in 2019, but 2020 data may provide insight on the effects grazing livestock have on selected soil properties, since increased time under conservation management may be required to build soil health.