Killing Annual Ryegrass

Annual ryegrass is an outstanding cover crop for building soil health.  The goal is a successful control following the first herbicide application.  There are several key factors to keep in mind when it comes to terminating this cover crop.

Temperature

- Glyphosate requires a minimum air temperature of 60 degrees

- Soil temperature should be 45 degrees

Timing

- Spray after the dew is dry and stop by mid-afternoon to allow 4-5 hours of sunlight for herbicide to translocate

Top Growth

- Allow your stand to be completely green and grow 6 to 12 inches tall; before the 1st node develops

- Allow 5-7 days after annual ryegrass has begun to actively grow before spraying.  A good indicator of this is your lawn- if you have not mowed your lawn, it is probably too early to be killing annual ryegrass.

Moisture

- Growing conditions should be good

Purdue specialist: Wait for warmer weather to terminate cover crops

"Producers who haven't yet terminated their cover crops should now wait for warmer weather before applying herbicide."  Bill Johnson, a  Purdue Extension weed scientist says.

- Click  here to read a press release from Purdue extension.