- A 110-foot downwind buffer is required when applying approved dicamba formulations on dicamba tolerant soybeans
- A new 57-foot omnidirectional buffer is required when applying dicamba to dicamba-tolerant soybeans in counties that contain an endangered species
- The applicator is responsible for determining the buffers and checking the endangered species bulletin prior to spraying dicamba
- If you don’t feel confident in your ability to apply these products on label—DON’T! If a little refresher or conversation is needed, please contact your local FS Crop Specialist for details.
Spring is off to a rapid start in some areas while off to a much slower and wetter start in others. Since most of the spraying season is in front of us, this is a good time to review the dicamba buffer requirements for use in dicamba-tolerant soybeans
DOWNWIND BUFFER
A 110- ft downwind buffer is required when spraying 22 oz of XtendiMax™ and FeXapan™ or 12.8 oz Engenia™ in dicamba tolerant soybeans. The key requirement to remember is that the 110 ft downwind buffer is ALWAYS mandatory! However, there are some items downwind that you can include in your buffer calculation. For instance, if a field corn is downwind, you can use 110 ft into the corn field as the buffer. This allows you to spray all the way to the soybean field border with dicamba. However, a downwind wooded area would be considered a sensitive area and would require a 110 ft buffer inside the soybean field to not be sprayed with dicamba. When determining buffer placement, consult the herbicide label and identify what areas are considered sensitive. Additionally, it is important to note that there are some instances where the label allows for more than 0.5 lb ae/a dicamba to be applied preplant or preemergence. With these higher application rates, the buffer requirement doubles to 220 ft.
OMNI-DIRECTIONAL BUFFER
In addition to the downwind buffer, dicamba applications in counties that contain an endangered species must use a buffer on the other three sides of the field. This buffer size is 57 ft and it is mandatory. Similarly to the downwind buffer, you can use the areas surrounding the field to be sprayed to determine where the buffer should be. If a corn field were on the upwind side of the field, the 57 ft buffer could be placed in the corn field. However, if a wooded area were upwind, the 57 ft buffer must be placed inside the field to be sprayed with that portion not receiving a dicamba application. If you must use an omnidirectional buffer, this still requires a 110 ft downwind buffer and a 57 ft buffer on the other three sides. The endangered species bulletin to determine if an endangered species exists near you can be found at: https://www.epa.gov/endangered-species/bulletins-live-two-view-bulletins.
STATE RESTRICTIONS
In addition to the federal label, some states have a 24(c) label which places further restrictions on the use of dicamba-containing products when used in dicamba-tolerant soybeans. The state of Illinois, for example, has some additional restrictions on its 24 (c) label. Some of the most noteworthy restrictions for IL would be no applications after June 30th, and that the applicator must maintain the appropriate buffer when spraying near an Illinois Nature Preserves Commission Site. Iowa also has a 24(c) that states that that the auxin training attended by the certified applicator must be approved by the Iowa Department of Agriculture and Land Stewardship and be offered by a registered auxin herbicide training provider.
FINAL THOUGHTS
Spring is off to a rapid start in some areas while off to a much slower and wetter start in others.Since most of the spraying season is in front of us, this is a good time to review the dicamba buffer requirements for use in dicamba-tolerant soybeans.