When it comes to crop protection and resistance management, commitment from everyone involved is key.
“Weed resistance management is complicated,” says Tim Ford, HELM Crop Solutions U.S. crop consultant liaison and regional sales manager for the south Delta. “We need engagement from all levels of the crop production side. From the farmer to the retailer to the supplier, to the company – there needs to be active engagement and attention to best practices across the board.”
According to Ford, the annual growing process starts with a carefully planned spring burndown that includes consideration of herbicide resistance and preservation of soil health.
Laying the foundation
Spring burndown applications are a cornerstone of crop production systems. This pre-planting intervention eliminates early-season weed competition and creates a clean slate for successful planting in three very important ways. Burndown helps a crop get established by removing the interference of weeds with seedlings during their most vulnerable growth stage. The process also improves stand uniformity and yield potential.
Understanding modes of action (MOA)
Knowing spring burndown is essential is one thing, but developing the most effective program is another. Resistance is one of the biggest threats to crops and something that should be considered when making herbicide decisions. In fact, research1 shows:
- Globally, there are 534 unique cases of herbicide resistance spanning 273 weedy species and 168 different herbicides across 21 of the 31 herbicide MOAs
- Herbicide-resistant weeds have been found in 98 crops across 72 countries
- More than 130 unique cases have been documented in the United States
So how do growers help manage this ongoing challenge? One way is to diversify the mode of action in the herbicides being applied. Reviton® is one effective option and has been proven to provide control of tough weeds like waterhemp, Palmer amaranth, giant ragweed and lambsquarters. It can be easily integrated into tank mixes and incorporated into pre-plant applications.
Be cautious when choosing a product and carefully evaluate the MOA. Due to products coming off patent, although some products may have different names, they may have the same MOA. Ford advises examining product labels to ensure the actual chemistry of the product is different.
Importance of active ingredients (AI) and application rates
Besides MOA consideration, growers need to tap into their math skills to evaluate herbicide options. The AI in an herbicide is the chemical compound responsible for controlling the target weeds. The rest of the formulation is made up of inert ingredients, such as solvents, surfactants, stabilizers or carriers that help with application, shelf life or absorption.
For example, when a label lists 30% Tiafenacil, that number indicates how much actual weed-killing chemical is in the product, not the total volume of liquid in the jug.
This AI percentage dictates how much product must be applied per acre to achieve the desired rate of control. “Chemical products usually have rate ranges for proper performance. Keep in mind, a product you bought two years ago may have had a higher concentration, which changes how effective today’s application will be,” says Ford.
How important is AI? Too low of a rate can lead to incomplete weed control, which can cause regrowth and herbicide resistance. Too high a rate can cause crop injury or environmental issues, especially in sensitive crops or adjacent fields.
Know Your Fields
The best-laid weed prevention programs aren’t effective if they are based on bad information. Keep records of dominant weed species and shifts in weed populations over time. Field scouting, particularly in late summer and fall, reveals which weeds are going to pressure the next crop cycle.
Different weeds emerge at various soil temperatures and depths. Knowing those patterns helps growers target herbicide timing. Other field characteristics that are important to understand and track are resistance history, the weed seedbank (dormant population of viable seeds in the soil) and micro-patterns.
Tap Into Resources
Effective weed management is a team effort that requiring input from across the value chain. Besides what the individual grower can and should do, other stakeholders should engage in decision-making.
“Good retailers and crop advisors are involved at the farm gate, not just with field trials,” says Ford. “They’re engaged in what their growers see in fields and help sort through marketplace complexity.”
Sound like a lot of work? It’s actually not when you consider the cost and time involved in a rescue program. A far greater return can be realized with a proactive investment of time to lay the right foundation.
To learn more or locate the HELM representative nearest you, visit Helmcrop.com.
