Emerged no-till soybeans (D. Lingenfelter, Penn State Weed Science)
We have received some calls inquiring about herbicide options for soybeans that have emerged, but the field did not receive a burndown herbicide or a residual was not applied yet. Weeds like dandelion, resistant marestail/horseweed, etc. will be very difficult to control postemergence in soybean. Also, many of the typical soil applied residual soybean herbicides (e.g., Valor, Authority, Sharpen, metribuzin, etc.) cannot be applied over the top of soybeans because of injury concerns. Below is a list of herbicides that have foliar broadleaf activity and/or residual activity and are allowed POST along with their labeled application timings and strengths. Unfortunately, most of these herbicides will not handle dandelion, burdock, curly dock, etc. very well. Keep in mind that products such as Dual Magnum, Outlook, Warrant, and Zidua will not control emerged weed, so they will need to be tank-mixed with herbicides that have foliar activity. Additional details about these herbicides can be found in Table 4-14 of the Mid-Atlantic Field Crop Weed Management Guide . This is not a comprehensive list and excludes generic products and herbicides that are mostly active on grasses and/or not typically applied POST.