Post-Emergence Control of Italian Ryegrass
Before top-dressing we want to terminate any weeds that could compete with our wheat crop. In this short video, Dr. Wes Everman tells us how to control our worst problem weed in small grains – Italian ryegrass.
December: If no pre-emergence herbicide was applied starting scouting.
January: If pre-emergence herbicide was applied start scouting.
February/March: Continue scouting since some Italian ryegrass biotypes germinate in March and compete with the wheat once we’re in grain-fill.
Be prepared to make your applications before the Italian ryegrass takes over.
Hoelon used to be our standard product, however, 95 to 98% of Italian ryegrass samples we tested were resistant to Hoelon, so we’ve effectively overused it.
We recommend using a residual herbicide in the post-emergence spray especially if you haven’t used a pre-emergence herbicide at planting. It takes a little pressure off of that post-emergence herbicide and allows for some control of any that may germinate in the spring.
Currently, we have 3 effective herbicides for post-emergence use on Italian ryegrass in wheat:
- Osprey – ALS inhibitor
- PowerFlex – ALS inhibitor
- Axial XL – ACC-ase inhibitor
We do have Italian ryegrass biotypes that are resistant to each one of these herbicides, but if we understand what bio-types we have and rotate our chemistries we can be effective at controlling it.