Diversifying corn production systems with living mulches in the southeastern United States

Living mulch (LM) production systems are gaining traction as an alternative to the use of annual cover crops in the southeastern United States, warranting research on the viability and functionality of this system. Our objective was to evaluate the benefits of LM in corn silage and grain production and to evaluate the potential of LM grazing during the corn (Zea Mays L.) growing season. The experiment was conducted in Spring Hill, TN in 2020 and 2021 and consisted of two mulch species, white clover (WC) (Trifolium repens L.) and a mixture of crimson clover (Trifolium incarnatum L.) and cereal rye (CCCR) (Secale cereale L.). Cull cows were used for the grazing periods (4 weeks before planting and after the harvest of corn). The study evaluated the botanical composition, mulch mass, nutritive value, corn silage and grain production, and cow average daily weight gain (ADG). The WC treatment had a greater weed control than CCCR. In 2020, when differences in mulch mass were observed, CCCR had greater mass than WC mass due to the weed presence. Meanwhile, in 2021, the mulch mass did not differ between WC and CCCR, with both treatments showing less mass in spring and early summer. Grain production was 30% less than silage in 2020 and 90% less in 2021. The ADG was only observed for WC (0.5 kg(-1)) paddocks. It was concluded that WC as LM has greater corn production than CCCR treatments. The LM for grazing is a beneficial strategy if feeding costs are greater than $2.22 head day(-1).