By Dwight Lingenfelter and John Wallace
As in the recent past, there are absolutely no new herbicide modes of action. All the newer herbicide products are simply new premixes or revised formulations of existing active ingredients. There are not many new products to discuss for this upcoming growing season. But here are several products, label updates, and products in the pipeline to consider.
Syngenta is modifying Acuron, Acuron Flexi, and Halex GT. Current formulations of Acuron and Acuron Flexi will be phased out after 2022. The new replacement products will be Acuron XR, Acuron Flexi XR, and Acuron GT. Primary changes include increased amounts of mesotrione (Callisto) and s-metolachlor (Dual) in the new formulations of Acuron XR and Flexi XR. Acuron GT is the same as Halex GT but will contain bicyclopyrone. The new formulations will likely not be used until the 2022 cropping season, but bulk tanks will start to be filled in late 2021.
Authority Edge 4.25SC (sulfentrazone [Spartan] + pyroxasulfone [Zidua]; groups 14, 15; FMC) has similar active ingredients as Authority Supreme but has a higher sulfentrazone load for use in any type of soybean. It will be soil-applied and have activity on both annual grasses and broadleaf weeds at 7-9 fl oz/A.
Impact Core 7.15EC (topramezone [Impact] + acetochlor [Harness]; groups 27, 15; AMVAC) will be used POST in field corn and provides foliar and some residual control of annual grasses & broadleaves. The typical use rates are 20 to 36 fl oz/A.
Kyber 2.64SC (flumioxazin (Valor) + pyroxasulfone (Zidua) + metribuzin; groups 14, 15, 5; Corteva) will be used PRE in any type of soybean and provides residual control of annual grasses and many broadleaves. Typical use rates from1-1.5 pints/A. Fierce MTZ (Valent) contains the same ingredients and ratios.
Gowan has acquired the rights to the active ingredients prosulfuron and primisulfuron from Syngenta. The acquisition includes product registrations and trademarks for Peak, Spirit, Beacon, and Northstar herbicides and related intellectual property and labels. This is good news since we typically recommend the use of Peak and Spirit to control burcucumber in corn.
Perpetuo (flumiclorac [Resource] + pyroxasulfone; groups 14, 15; Valent) can be used post in any type of soybean and provides foliar control of certain broadleaf weeds and residual control of many grassy and broadleaf weeds. The use rate is 6-10 fl oz/A.
ProClova (florpyrauxifen (aka Rinskor active) + 2,4-D; group 4; Corteva) will be labeled for use in grass pastures and hayfields to control or suppress many broadleaf weeds such as: ironweed, cocklebur, wild carrot, buttercup, biennial thistles, ragweeds, plantain, poison hemlock, dandelion, marestail, horsenettle, and others. It is safe on forage grasses AND does not kill white clover. The typical rate will likely be 1.5 pints/A. It has no grazing restrictions and does not have issues with herbicide residues in manure and hay like Milestone or GrazonNext products. ProClova is not yet registered but has an anticipated launch in 2021.
Reviton 2.83SC (tiafenacil (aka Tergeo); group 14; Helm) can be use in a burndown program before field corn, soybean, or wheat. Corn or wheat can be planted immediately after application; wait 14 days to plant soybean and at least 4 months to plant other crops. It has a low use rate (1 to 3 fl oz/A) and can be tankmixed with other herbicides such as glyphosate to broaden the control spectrum. MSO or COC plus AMS must be added to the spray solution for effective control. Reviton is similar to Sharpen and will compete with it for market share, however it is less active on marestail but has better grass control vs. Sharpen.
Roundup PowerMax3 (Bayer) is a new, high load (4.8 lb ae), unique adjuvant, glyphosate formulation. PowerMax3 at 19 fl oz = 22 fl oz of PowerMax (0.75 lb ae/A).
Shieldex 3.33SC (tolpyralate; group 27; SummitAgro) is a newer, low use rate (1 to 1.35 fl oz/A), HPPD-herbicide that controls annual grasses and broadleaves postemergence in field and sweet corn. It is very similar to Armezon or Impact. It will typically be tankmixed with atrazine to improve the control spectrum.
Sinate 2.57L (topramezone [Impact] + glufosinate [Liberty]; groups 10, 27; AMVAC) can be used postemergence in field corn and sweet corn varieties that have the LibertyLink trait and controls many annual grasses and broadleaf weeds. Typical use rates are 21 to 28 fl oz/A.
Paraquat updates: Anyone using products containing paraquat (i.e. Gramoxone and all other generic formulations) must now complete an EPA-mandated training before application. The following are items related to the new label for paraquat products:
- Only certified applicators, who successfully completed the paraquat-specific training, can mix, load or apply paraquat
- No longer allow application “under the direct supervision” of a certified applicator; registered technicians cannot apply
- Restricting the use of all paraquat products to certified applicators only
- Applicators must repeat training every three years
- The EPA website has the required paraquat video training (users must create an account with user-name and password). For those who are unable to do the training online, EPA will have a non-web-based training format available.
- Refer to the EPA paraquat website for more information and frequently asked questions.
In addition to the training, EPA requires that paraquat products be contained in a closed system. Over the next year or so, manufacturers will begin placing special lids on 2.5-gallon jugs and a necessary adaptor/receptacle will need to be installed on your sprayer in order to pour this herbicide into the sprayer tank. These new jug caps cannot be removed or opened by hand. Mini bulk tanks will also have special connectors on hoses to maintain a closed system into the sprayer tank. More details will be released once these lids and adaptors become more widely available.
Newer soybean technologies
Understanding the differences: With all the newer soybean technologies on the market, it can be somewhat confusing to know the differences between them. Make sure you know the differences between the unique variety options before you purchase. Also, consider that other “standard herbicides” that are labeled for use in soybeans still can be used with any of these as well. Here is a quick overview of their trait packages and some related herbicides:
- Roundup Ready 2 Yield soybeans are tolerant to glyphosate only.
- Roundup Ready 2 Xtend soybeans are resistant to both glyphosate and dicamba products labeled for this use. XtendFlex soybeans are resistant to glyphosate, dicamba, and Liberty and will be available for the 2021 growing season.
Last year, the EPA re-registered the Xtend-specific dicamba products until Dec. 2025. Engenia 5L (dicamba-BAPMA salt; BASF) and Xtendimax 2.9L (dicamba-DGA with Vapor Grip Technology; Bayer) are the only two dicamba-only herbicides that can be used in Roundup Ready 2 Xtend (Flex) (dicamba-tolerant) soybeans. Each of them contains the group 4 herbicide dicamba and are now classified as “Restricted Use Pesticide” (RUP) and thus require special dicamba-specific training annually to purchase and apply them. Some major updates to the new label include: the inclusion of a drift reducing agent (DRA) and volatility reducing agent (VRA) in the spray mix; applications can be made only until June 30 or R1 soybean stage (whichever comes first); and a 57’ omnidirectional buffer and 240’-310’ buffer for sensitive areas downwind.
Tavium 3.39CS (dicamba + s-metolachlor [Dual Magnum]; groups 4 and 15; Syngenta) is a premix and will provide post broadleaf control from dicamba and residual annual grass and broadleaf control from Dual in Xtend soybeans. Their prime targets will be Palmer amaranth and waterhemp.
Source : psu.edu