Artificial intelligence takes on weeds

Spot-spraying technology powered by artificial intelligence (AI) is making it possible for farmers to slash herbicide inputs.

“We were able to save 86% of the product that we were typically spraying,” says Laverne Gill of Medicine Hat, Alberta. “We used about 14% of what we would normally use to do a blanket spray” this spring before seeding by employing the Weed-IT Quadro system.

Shabeg Briar, research agronomist at Olds College, found similar savings in 2021 and 2022 using a Weed-IT Quadro system in replicated research strip trials. The Weed-IT cameras were able to identify weeds and send a signal to the nozzles to spray only green plants in brown areas, Briar explains. 

The system wouldn’t help for in-crop weed control but “we saved about 80% to 85% of the spray volume in strips with spotty weed infestations and achieved a similar level of control,” he adds.

Weed-IT

Red LED lighting was introduced in North America by Weed-IT Quadro distributors for green-on-brown weed detection and control in September 2022. Distributors are AgriTech America in Bozeman, Montana, and Croplands Equipment Canada in Calgary, Alberta.

Weed-IT Quadro, built in the Netherlands by Rometron, was released in late 2019 with blue LEDs. Since then, new red LEDs and optics have outperformed the earlier system for consistency, efficiency, and predictability. All three are essential for effective spot spraying with optical technology. 

The modular Quadro Red system has optical sensors on 40-inch spacing and individual nozzle control. A specially designed Millennium aluminum spray boom kit was developed to ease the retrofit of Weed-IT to a wide range of self-propelled sprayers. With installation, the turn-key cost for doing a 100-foot boom is about $270,000. 

Gill says he tested use of the Weed-IT Quadro for fall spraying in 2022 and noted “100% effectiveness on the weeds that I sprayed.”

Gill, his wife, and two sons direct-seed about 5,200 acres in a dry, brown soil zone prone to drought in western Canada. They grow spring wheat, durum wheat, barley, lentils, field peas, and mustard on a three- to four-year rotation. 

They have a 2012 3330 Case IH Patriot sprayer with a five-section, 100-foot rear-mount boom and 1,000-gallon tank.

His nozzles were active only when passing over weeds seen by the sensor array, and he was applying a full rate of glyphosate, not the usual half-rate.

“Weed-IT allows you to up the rate so you’re not pinching pennies,” Gill says. “We knew a full liter of Roundup would be more effective on what we were spraying, and it was.”

Before purchasing the precision spraying system, Gill and family calculated the return on investment. The math showed the Weed-IT technology would pay for itself in reduced herbicide bills in 30 months. It’s working out.

“On one day this spring, we saved $11,000 in spray and another day we saved $16,000…. It doesn’t take many days like that to justify the system,” he says. “We’re able to up the dosage, hit weeds hard, so they’re not developing chemical resistance, spraying the weeds that are actually there, being environmentally conscious of how much we’re putting on the ground, and still not spending anywhere near what we were spending before.”  

Symphony vision

AGCO is close to commercial launch of the Symphony nozzle pulse width modulation (PWM) system, says Jason Stoller, senior product manager for Illinois-based Precision Planting. He describes it as “a suite of solutions for intelligent spraying.” 

In January 2020, Precision Planting announced it was entering the sprayer business with products to improve operation and data collection of sprayers. 

“The Symphony PWM nozzle control system will be offered for sale this fall, and we hope to conduct our beta of the Vision system this coming spring,” says Stoller. 

Symphony PWM nozzle control will allow the sprayer to maintain constant pressure while changing speed or application rates. It also features swath control and turn compensation. 

Symphony Vision is an upgrade.

“Assuming we have successful beta data, it’s intended to commercially launch Vision for row crops soon after. Small-grain support would follow quickly. Adding crops and regions is really about just training the model,” he says. 

Symphony Vision uses edge-based artificial intelligence (AI) to achieve green-on-green or green-on-brown applications. The AI vision modules are spaced across the entire spray boom. 

“We have our AI models classifying and isolating crop from weed and even from weed categories. We separate broadleaf weeds from grass weeds from crops, and the system controls off those detections,” explains Stoller.

When it detects a weed in the spot-spray mode, nozzles above that weed will turn on. AI determines which spray rate will be applied, based on weed size, before it passes. Vision then shuts off automatically until another weed is detected. 

Significant savings can be expected with operation of the Symphony Vision system.

“Our beta testing in real field applications is indicating a significant reduction in herbicide. We’ve seen examples in central to southern Illinois saving up to 80% of pre- and post-applications of contact herbicide,” Stoller says. 

Spraying time efficiency will also improve. Traditional sprayer refill can take 20% of an operator’s day. Symphony Vision can enable the operator to maintain speed and move on to the next field, refilling less often. 

“Ultimately, a farmer will go through much less herbicide and go through more fields per day,” Stoller says. 

Competitors coming

Other spraying technologies are coming to the fields. 

Israeli ag tech pioneer Greeneye Technology launched U.S. retail sales in early 2022 followed in August with benchmarked performance results from University of Nebraska-Lincoln field trials. In January 2023, Greeneye announced collaboration plans with Farmers Business Network to sell a precision spraying retrofit kit in the United States.  

AGCO has a second precision spraying system approaching market release. In April, Bosch BASF Smart Farming and AGCO Corp. announced plans to commercialize smart spraying technology on Fendt Rogator sprayers. It will be available in 2024 for corn, soy, cotton, sugar beet, sunflower, and canola. Small grains and other crops will be added later. 

John Deere entered the market in March 2021 with See & Spray Select technology for targeting and spraying weeds on fallow ground. This was followed in 2022 with See & Spray Ultimate, an in-crop spray technology combined with a dual-product solution system. This year, Deere introduced the first add-on kit, See & Spray Premium, using a vision system powered by artificial intelligence.