Editor's note: Updated 6/11/2020

Cotton and soybean growers have options, including continued potential use of XtendiMax, Engenia and FeXpan herbicides, says Larry Steckel, University of Tennessee Institute of Agriculture Extension weed specialist, in reaction to the recent Ninth Circuit Court of Appeals order vacating EPA’s pesticide registrations of those three products.

An EPA order released June 8 clarified how the ban will affect cotton and soybean growers and “mitigates some of the devastating economic consequences of the Court’s decision for growers, and particularly rural communities….”

According to the release, EPA’s order addresses sale, distribution, and use of existing stocks of XtendiMax, Engenia, and FeXapan.

Also, the order states:

1. Distribution or sale by any person is generally prohibited except for ensuring proper disposal or return to the registrant.

2. Growers and commercial applicators may use existing stocks that were in their possession on June 3, 2020, the effective date of the Court decision. Such use must be consistent with the product’s previously-approved label, and may not continue after July 31, 2020.

“EPA says we can use what we have on hand,” Steckel told Farm Press in an interview June 9. “Availability will depend on farmer to farmer and retailer to retailer. We have a good bit of Engenia and XtendiMax applied. And we can use it for a bit yet.

Related:EPA issues a key order for farmers in dicamba case

“Most of Tennessee’s cotton has had one application over the top,” he says.

Soybean producers may use Xtend if they have it on hand, if the Tennessee Department of Agriculture approves it, he adds.

In a June 9 blog post, Steckel put the ban in perspective.

“Our state will have roughly 2 million acres of soybeans and 300,000 acres of cotton. My best estimate is that roughly 90% of those 2.3 million acres are in Xtend crops.”

He says supply of the banned dicamba herbicides will be an issue and “not be enough… to spray all the acres of cotton and soybeans once let alone twice.”

He says Tavium, a premix of XtendiMax and Dual Magnum, was not included in the lawsuit and therefore not banned. “Tavium still will be labeled but I am told supply of that herbicide is tight.”

He told Farm Press that for cotton, “from here on out, go with Liberty. It works best in hot, humid conditions and is good on pigweed that escapes dicamba.”

He’s seen a lot of escapes. “I have been disappointed with dicamba control,” he said. The issue has been an ongoing concern for several years.

See more information on weed escapes and rates in Steckel’s blog at https://bit.ly/2YlfVgm.

He says farmers with a short supply of Engenia or XtendiMax might consider swapping to a soybean with a different herbicide resistant trait platform. “However, I have visited with several seed retailers and most say getting any supply of soybean seed in an Enlist or LLGT27 trait is difficult this late in the season.”

Louisiana

Daniel Stephenson, weed specialist at the LSU AgCenter in Alexandria, La., says controlling Palmer amaranth without dicamba “will be a fight, a harder fight.”

Timing will be crucial, he adds. “Controlling weeds without dicamba will require applying herbicides when weeds are small. But that is the case even with dicamba. Timing is the number one consideration, regardless of the herbicide used.”

He emphasizes that “dicamba is not a silver bullet; it’s just a tool, even when it’s available, it’s just one more wrench in the toolbox.”

Stephenson says dicamba and other products must be part of a weed management system. Residual herbicides, he adds, are critical parts of that system.

In the absence of dicamba, for soybean producers who do not have the banned products on hand, he says Tavium remains available. Group 15 herbicides such as Dual Magnum, Warrant and several products containing the active ingredient in Zidua also provide options.

He adds that PPO herbicide resistance has not been a significant issue in Louisiana, so Blazer, Reflex and Cobra remain viable options.

“Without dicamba, producers are growing a Roundup Ready soybean crop,” he says.

He says cotton farmers can use Liberty, Dual Magnum, and Warrant. “But they need a residual.”

Mississippi

Trent Irby, Mississippi State Extension soybean specialist, says an MSU publication specific to Palmer amaranth control includes Roundup Ready, LibertyLink, or Conventional soybean production systems (see https://bit.ly/37ilMqR).

“With that said, the recommendation for what weed control options would look like in the absence of approved dicamba formulations for use in Roundup Ready 2 Xtend soybeans reflect the Roundup Ready programs listed in this publication.

“The take home point for weed management, for Palmer amaranth in particular, is use of residual herbicides. With a limited postemergence herbicide toolbox, timely application of residuals is necessary for successful weed management.”

Crop consultant Trent LaMastus, Cleveland, Miss., says the ruling puts farmers in a bind.

“The timing could not have been worse,” he said on June 9. “We have a late crop and a lot of farmers are just now getting herbicides out. Some were just wrapping up planting soybeans before the news came out about dicamba.”

He says farmers have already made and implemented production decisions regarding herbicide-tolerant varieties. Losing the ability (while in season) to use dicamba  puts those plans in disarray.

Options for soybeans will be limited, he says. “If a grower didn’t have dicamba he intends to use on hand when the ruling came out, he is in a tight spot. I anticipate some bad weed hot spots that nothing else will work on. We could see abandoned fields.”

He says land inundated by floods the past two years pose significant challenges.

“Producers finally got the land exposed and planned to use dicamba crops. But they have had two years with no herbicide on the land and covered by flood water. Imagine the weed pressure and not being able to use the technology.”

He says Tavium is an option. “Liberty is also available for growers short on their intended dicamba choice.”

He says another, less than ideal, option might be “chopping in rare cases. Also, producers should be ready to break their hooded sprayers out of the weeds and consider something hot.”

LaMastus says conditions could get dicey in a hurry. “It only takes a couple of weeks for pigweed to take over a crop. With recent rain and wind, it has been challenging to get ahead of or keep up with weed pressure. Residual herbicides will be more important than ever.”

He expects to see trouble spots and lost production. That loss will pile on yield potential already threatened by late planting and multiple red-banded stink bug infestations.

Little effect

Marks, Miss., farmer Gerald White expects the dicamba ruling will have little effect on his operation in 2020.

“I had some product on hand before the ruling,” he said in a Farm Press interview. “I really don’t expect a lot of impact from this area in 2020. Most of the farmers around here had products on hand and a lot has already been applied.”

He says the dicamba herbicides will be up for re-registration in December, so availability for 2021 was already uncertain. “We just have to wait and see how it plays out.”

White said in early June he’d finished planting cotton. “Now, we have too much water from the tropical storm (Cristobal). We hope it moves off in the next 24 hours.”

In the EPA announcement released June 8, EPA Administrator Andrew Wheeler questioned the timing of the ruling. “At the height of the growing season, the Court’s decision has threatened the livelihood of our nation’s farmers and the global food supply,” he said. “Today’s cancellation and existing stocks order is consistent with EPA’s standard practice following registration invalidation, and is designed to advance compliance, ensure regulatory certainty, and to prevent the misuse of existing stocks.”

In the meantime, it’s up to farmers, retailers and consultants to work through the aftermath of the decision that comes at a time when markets struggle from ongoing trade issues, the pandemic and weather uncertainties that defy regulation and management.