Roundup Ready 2 Xtend soybeans (dicamba-tolerant) were deregulated and approved in 2015 and received export approval in 2016. In November 2016, US EPA registered the dicamba product Xtendimax (DGA salt) with Vapor Grip Technology for weed control in Xtend soybeans. BASF's Engenia (BAPMA salt) received federal approval in December and DuPont is expected to market FeXapan (DGA salt) with Vapor Grip Technology as well. Last week, the Pennsylvania Department of Agriculture approved Xtendimax and Engenia for Xtend soybeans in Pennsylvania.
Xtend soybeans were developed by Monsanto to allow pre or post applications of dicamba (the active ingredient in Clarity) on soybeans. These varieties are also stacked with the Roundup Ready trait. The Xtendimax and Engenia labels for use on Xtend soybeans are conditional, 2-year supplemental labels however, they can be prolonged if there are few or minimal problems in the first two years or could be revoked if significant problems arise.
In order to reduce drift and the other negative impacts to non-target areas, these initial labels is quite restrictive, not allowing for tank-mixing, only a single nozzle type is recommended, boom height is limited, and sprayer speed and wind speed are restricted. Also, depending on the landscape setting, field buffers must be included if susceptible crops are present and downwind at the time of application. In addition, the application cannot occur if wind is blowing in the direction of specific crops such as tomatoes, vine crops, grapes, and others. The applicator is responsible for any drift of these products to off-target sites.
Guidelines for using Xtendimax and Engenia as burndown applications are similar to "in crop" and these guidelines can change periodically as new information is acquired. Refer to their labels and websites for additional information and updates online by Monsanto and by BASF.
The weed science extension program at Penn State sees value particularly in a burndown setting for marestail control with this new technology. However, we are less excited about in-crop applications and are concerned about off-target movement, sprayer cleanout, etc. and would prefer to first learn from the experiences of other states and regions in 2017 that need this technology more.