Italian Ryegrass can stall winter wheat growth if efforts aren’t made to control it, according to Kansas State University Extension agronomists. Field tests conducted in southeast Kansas to evaluate fall and spring postemergence herbicide treatments for Italian ryegrass control in hard red winter wheat showed that solid treatment programs can increase wheat yields by as much as 40%.
In the K-State field tests, fall postemergence treatments were applied to two-leaf wheat and one-to-two leaf Italian ryegrass in late November. Spring postemergence treatments were applied to tillered wheat and Italian ryegrass in mid-March. The experiment was a randomized complete block design with three replications. Wheat injury and ryegrass control were evaluated through the season and wheat was harvested for grain yield. Italian ryegrass control was better with fall than spring treatments of various herbicides.
Bob Scott, Extension weed scientist, University of Arkansas, adds that it’s important to remember some cultural practices that can help manage ryegrass problems. “First of all, a single year of fallow or crop rotation and not allowing any ryegrass to go to seed is equivalent to about 90% control of ryegrass the following year,” he says. “In addition, simply letting the first ‘flush’ of ryegrass germinate and emerge prior to planting, then killing it either with tillage or, preferably, chemicals is also equal to about 80-90% ryegrass control.