Prepare for weeds, pests & disease
Getting ready for the planting season can feel like going to war against weeds, pests and crop diseases. To help farmers gear up for battle, Matt Pinckney, Syngenta retail representative, presented “Maximizing Corn & Soybean Yields” at the recent A.N. Martin Open House. Based in Clyde, NY, A.N. Martin installs grain storage and handling systems.
“It takes more than $450 million and 14 to 17 years of research to bring just one new product to market,” Pinckney said. “Every new product starts with your customer in mind: What challenges are they facing? How can we help them yield more and deliver higher quality?”
The process starts with biological screening (one to two years); field screening (two to three years); biological, toxicological, ecological and economical profiling (three to four years); registration submission/process refining positions and launch preparation (two to four years); and finally launch and sales (one to four years).
Pinckney introduced a new insecticide from Syntenta, PLINAZOLIN. Although not yet offered for sale, PLINAZOLIN (active ingredient isocycloseram) features a mode of action in IRAC Group 30. The broad-spectrum insecticide will control beetles, corn rootworm leafminers, Lepidopterous pests, mites, psyllids, stink bugs and other true bugs and thrips.
The proposed registration is for a wide range of crops, including row crops, vegetables and specialty crops. It is not systemic and is highly rainfast and UV stable. Pinckney anticipates New York State certification by June or July 2026.
“Corn rootworm is really taking off,” he said. “This is a tool that can be used in rotation.”
Syngenta plans to use PLINAZOLIN in Zivalgo™, Incipio™, Opello™ and VERTENTO. Zivalgo is for stone fruit protection from codling moth, obliquebanded leafroller, Oriental fruit moth, plum curculio, pear psylla, thrips and mites (and in potatoes, Colorado potato beetles).
Incipio will be for shielding Brassicas from diamondback moth, cabbage looper and imported cabbageworm. For leafy Brassica, it’s indicated for cabbage looper, diamondback moth and thrips.
Opello will target corn rootworm, white grubs and wireworms in corn. “Opello you can put right in with a topical fertilizer,” Pinckney said.
VERTENTO will protect onions from thrips.
Pinckney also spoke about weed management through herbicide options. “Weed management is more than simply killing weeds,” he said. “Its focus is on minimizing weed competition throughout the development of the crop and delivering more of the crop’s yield potential.”
By minimizing the weed seed bank, farmers can reduce the impact of weeds. For optimal weed control, farmers need to consider the timing of their weed control measures, duration of weed control and minimizing the risk of a weed control failure.
“Commercially acceptable weed control won’t result in impacting crop yield,” Pinckney said. “The standard varies by both crop and weed species. Typically, it’s 90% control.” In a study at Ohio State, researchers found that seeds for weeds such as for pigweed, marestail and giant ragweed don’t germinate every year. But they multiply very quickly, Pinckney added. It pays to stay vigilant, as a single plant one year can cause catastrophic yield impact a year or two later. To effectively manage weeds, operators need to identify the type of weed, consider the impact of the weed and understand its lifecycle.
Factors affecting weed control include identifying the weed, timing of application, calibration of spray equipment, soil type and pH, organic matter, soil moisture, rainfall, temperature, tillage type, weed pressure, weed seed bank, herbicide mode of action and weed resistance issues.
Pinckney said it’s important for farmers to correctly identify their particular weed concern and match it to the correct herbicide.
“Know your target before you choose your product,” he said. “A lot of products have resistance lists. Labels are only updated every five to 10 years.”
He said it’s vital to address marestail and waterhemp before emergence. “Timing is everything,” he said. “Treat the seed, not the weed. It’s the most vulnerable stage. A strong residual program is key.”
He advised starting the season with a residual herbicide to provide a solid foundation for season-long weed control, minimizing early season weed competition in the crop and maximizing yield.
“Delays in post-emergence herbicide applications reduce yield,” Pinckney said. “Incorporating a post-emergence residual herbicide is important for late season weed control.”
Operators must have activating rainfall within five to seven days of applying herbicides, with more time if it’s early spring.
“If you’re higher in organic matter, utilize that higher application rate,” Pinckney said. “Make sure you’re paying attention to the label … Tillage resets weeds by killing emerged weeds and disrupting seeds that have started to germinate, so apply residuals soon after the last pass.”
Susceptible herbicide groups include triazines such as Atrazine and Metribuzin.
Even with the best planning, sometimes herbicide application doesn’t pan out ideally. If good rainfall activation is followed by lengthy dry weather, it helps to scout for weed “escapees” while there’s still time to apply a post rescue.
“Be sure to use rates that match soil texture and organic matter,” Pinckney said. “Heavier soils bind up more herbicide so less is available in soil solution for weeds.”
Understanding weed lifecycles can help farmers plan better. Pinckney said crabgrass emerges most in July and August. For fall panicum, August is most prominent, followed by June and July. Lamb’s-quarter is early, emerging in April and May. Foxtail is also early, with emergence strong all season.
A field infested with weeds can be cleaned up, but its lost yield potential cannot be regained, Pinckney said.
“Pre-emergence herbicides help you to start clean to maximize yield,” he said. “Overlapping residuals with a two-pass herbicide program helps you stay clean and minimize competition of late-season weeds.”
Some farmers push back against the idea of two passes because they’re busy spraying beans or and don’t want to clean out the sprayer. But he said that although the sprayer must be empty, it won’t need to be cleaned as long as the products are both Roundup ready.
Late season grasses can also lessen yield. Pinckney said that the length of control for the residual used will make a difference. Dual Magnum lasts 48 days. AAtrex and Princep last 60.
“Extend the half-life with a two-pass system,” he added.
This year, Pinckney anticipates a continuation of tar spot problems in corn. “It’s here and we’re starting to get concerned about it,” he said. “We need to manage it.”
There’s also northern corn leaf, anthracnose stalk, anthracnose leaf, common rust and gray leaf spot to watch for.
“All affect yield and quality,” Pinckney said. “Foliar diseases decrease photosynthesis, cause stalk cannibalization and can kill or cause early dry down.”
The spread of these corn diseases relies upon the right environment, a susceptible host and the presence of the pathogen. Disease resistant hybrid seed provides some protection, along with fungicide applied at silking.
