Management considerations for hailed out wheat

There were several hail reports during the months of June and July in Kansas, impacting wheat that had not yet been harvested. Hailed out fields require different management considerations depending on hail intensity. A hail event might affect the subsequent crop as well, especially in the case of wheat where the hail results in many seeds that might later become volunteer wheat.

Where wheat suffered hail damage after heading, volunteer wheat often emerges even before the existing field is harvested – as much as two to three weeks or earlier than it would normally emerge. If volunteer wheat is not controlled throughout the summer and is infested with wheat curl mites, the mites will survive until fall and could infest newly-planted wheat at that time. Wheat curl mite infestations in wheat often lead to wheat streak mosaic infections.

Where wheat was hailed out and volunteer has already emerged at the time of harvest, control should begin immediately after harvest if possible. This is true even for fields that got hailed out relatively early during grain filling, as wheat grain at soft dough or later stages of development already has the potential to germinate. If volunteer has emerged and is still alive shortly after harvest in hailed-out wheat, wheat curl mites could easily build up rapidly and spread to other volunteer wheat that emerges later in the season.

If this early-emerging volunteer is controlled shortly after harvest, that will help greatly in breaking the “green bridge”. However, if more volunteer wheat emerges during the summer, follow-up control will still be needed. While hailed out fields may require one more field pass than normal to control volunteer wheat, it will help prevent even bigger problems down the road. It should be noted that grazing volunteer is not an effective option because there is green wheat material left and the mites can be living in that material.

On average, WSMV causes $75 million in losses to Kansas wheat farmers each year. Wheat Streak Mosaic Virus can cause a yield loss of more than 80 percent. If we take preventative measures now, future yields will improve exponentially. Prevention is the only method, so Stop the Streak now.

The virus is spread by the wheat curl mite, which feeds on wheat and other grasses.

The best way to prevent the spread of the wheat streak mosaic virus is to remove volunteer wheat and other grassy weeds. Volunteer wheat must be completely dead and dry for two weeks before planting a new wheat crop. Volunteer wheat and other grassy weeds can be killed with herbicides or tillage.

A second management practice to limit the spread of the virus is to avoid early planting. Plant wheat after the “hessian fly free date” for your area. In some areas in western Kansas where there is no Hessian fly-free date, farmers should choose to wait until late September or October to plant their wheat. Planting after these dates will reduce the risk for the new wheat crop and reduce wheat curl mites from moving to new locations of wheat.

In addition, farmers can choose a wheat variety with resistance to the virus or the wheat curl mite.

Read more from K-State Agronomy: https://webapp.agron.ksu.edu/agr_social/article/management-consideration...