First-Ever Solid-Encapsulated Herbicide For Pre and Post Weed Control in Corn

Ask corn growers what their No. 1 weed problem is today, and it’s likely at least one of these three – Palmer amaranth (pigweed), waterhemp or common ragweed – will be listed in their response.

In an AgWeb poll last September, when asked what their top weed nemesis on the farm was, nearly 400 growers responded. The results: waterhemp took the top spot, earning 35% of farmers’ votes. Palmer amaranth clinched second place with 15% of the votes. Ragweed tied with horseweed (marestail), with each capturing 9% of farmers’ votes.

The amount of consternation these and other weeds cause in fields across farm country is evident in the amount of money growers spend to address them, according to Wade Firestone, U.S. crop product manager for BASF.

“Farmers spent $2.2 billion dollars to control weeds in cornfields in 2021,” he told attendees of the company’s 16th annual Science Behind Event on Wednesday afternoon in Orlando, Fla., prior to the start of the 2023 Commodity Classic.“They’re spending more because resistance is increasing,” Firestone said. “In 2018, some states reported resistance to seven sites of action (SOAs). Resistance is growing because farmers are spraying different products with the same active ingredients.”

A New Solution On The Way

BASF expects to help corn growers address the issue of over-application of some active ingredients (a.i.) in the next calendar year, pending EPA approval, with its new weed-control solution: Surtain herbicide. Surtain controls up to 79 broadleaf weeds and grasses including the three noted offenders, Palmer amaranth, waterhemp and ragweed, the company reports.

BASF has invested more than a decade of research and development in readying Surtain for farmer use, according to Firestone.

“We’ve spent 10 years of R&D, hundreds of lab trials, hundreds of research trials – 5,200 different treatments – to get us to where we are today,” he said. “What this brings us to is a solution for the grower that maximizes residual endurance, providing up to eight weeks of residual control on those three weeds,” he added.

Solid Encapsulation An Industry First

Surtain will give farmers the flexibility for a preemergence or early post application, according to Daniel Waldstein, technical marketing manager. What makes that possible is an industry first – solid-encapsulated technology, a patented and proprietary process unique to BASF.

“We started with liquid encapsulation, which is the typical method for encapsulating herbicides, but it just didn't work; we couldn't get the level of crop safety we wanted,” he said. “So we used a novel concept, solid-encapsulation technology which is new to the market. That enables us to not only get the pre-post application flexibility, but it also gives us excellent residual weed control.

“If farmers make a pre application on conventional tillage, it's an all-in-one jug solution to weeds. They won't necessarily need to add anything in terms of a third chemistry to the tank,” he added.

Waldstein said Surtain contains two active ingredients to combat weeds – saflufenacil, a Group 14 PPO inhibitor, and pyroxasulfone, a Group 15 growth-inhibiting product. He said pricing will be announced closer to market introduction, which the company anticipates for 2024.

This summer the herbicide will be applied in large-scale field trials for agronomist and farmer consideration.

“We will have it at most major universities, in our technical service trials and at our showcase plots throughout the entire Midwest,” Firestone said. “Come join us out in the field, so we can show you what we're so excited about with Surtain herbicide and how it's going to help address the weed issues that growers are facing today.”

Firestone reviewed what he called the three pillars for Surtain – its residual endurance, a unique chemistry combination, and flexibility of use. Here is a summary of the pillars:

Residual Endurance:

• Residual control or suppression of 79 grass and broadleaf weeds with excellent control of waterhemp and giant ragweed
• Attacks weeds at their weakest stage: a pre application before emergence equals one growing point versus a post application when weeds have many growing points
• Preserves yield potential with proactive weed control: 6-inch weeds cause 7% yield loss in corn.

Unique Chemistry Combination:

• First solid-encapsulated herbicide technology – a patented and proprietary process unique to a BASF residual PPO herbicide
• Resistance management tool: two effective sites of action for residual control on waterhemp without HPPD inhibitors.
• Enhanced liquid fertilizer compatibility with UAN and ATS. 

Flexible Application Options:

• New Formulation Technology: residual PPO chemistry (Group 14) can now be applied early post in corn. Increased application window up to three weeks after planting. 
• Use full rates pre or early post and follow with any labeled product on the market, if needed.
• Tank mix partners: Farmers will be able to customize the application to fit their needs to control specific weeds.