Italian ryegrass is becoming one of the most troublesome weeds in the Mid-South for many reasons, including herbicide resistance. Herbicide-resistant Italian ryegrass is particularly problematic due to its ability to survive applications of glyphosate and clethodim. The most effective way to control ryegrass is to prevent emergence by applying residual herbicides in the fall. Tennessee has many relatively hilly fields, which raises concerns about soil erosion without some winter plant coverage. Although fall residual herbicides are effective for controlling ryegrass, the limited time available during the busy harvest season often makes applications impractical.

Our research suggests that a fall residual herbicide can provide effective control of Italian ryegrass. Command, along with herbicides like Zidua, Anthem Flex, and Dual Magnum, were among the top-performing treatments in terms of Italian ryegrass control in Madison County in 2024. The variance in the level of control of Italian ryegrass is mostly weather-dependent. Some herbicides, such as Anthem Flex or Zidua, require little rainfall to become activated. Others, such as Dual Magnum or Command, require more rain to be activated.