During this winter, producers should start planning their program for controlling the weed kochia in corn and grain sorghum.
The spread of glyphosate-resistant (round-up resistant) kochia populations throughout western Kansas and the difficulty growers have had controlling these populations suggest that control measures should begin prior to emergence of kochia.
According to the weed specialists at K-State, huge flushes of kochia emerge in late March and into April.
Applying 16 ounces per acre of Clarity/Banvel/generic Dicamba with a pound of Atrazine around mid-March before the kochia has emerged could provide significant control of early flushes of kochia.
The addition of 2,4-D will help control winter annual mustards that have emerged. This will make subsequent kochia control measures that are applied later in the season more effective.
When treating kochia with burndown or in-crop herbicides, spray early when the plants are about 1 to 3 inches tall. Always remember to read and follow label directions.
More information on kochia control for corn and grain sorghum was provided in the recent K-State Extension Agronomy update. If you are not receiving these email updates but would like to, simply email Jonie James at email@example.com, and request to be added to the list.
Jonie James is a McPherson County Extension agent for agriculture.