John Deere has added variable rate capabilities to its See & Spray targeted spraying technology, extending the system beyond switching nozzles on and off to changing the dose it applies as it travels across the field.

The upgrade matters because it changes what the machine can do between the crop rows, not just within them. Until now, See & Spray has made its name on detection: cameras identify weeds against the crop backdrop, and the system fires herbicide only where a target appears. Green-on-green and green-on-brown detection lets operators cut total herbicide volume sharply compared with a blanket pass, because the boom treats detected plants rather than the whole sprayer width.

Variable rate moves the logic one step further. Instead of a single fixed dose for every detected weed, the system can now modulate what it applies according to the target it has classified. A small rosette weed and a large mature one present different challenges, and a dose that kills one may be more than the other requires. Matching dose to target is the same agronomic principle that underpins variable rate fertiliser spreading, applied here to chemical weed control on a plant-by-plant basis.

What does the change mean for spray planning?

For growers already running See & Spray, the question is how the new capability fits existing programmes. Variable rate application sits naturally alongside the reductions the technology already delivers, since dose control compounds with spot treatment to lower total product use per hectare. Operators who have built weed maps and treatment reports from See & Spray passes gain another lever on input costs without changing the machine's core detection workflow.

For those considering the system, the calculus shifts as well. Resistance management increasingly drives herbicide decisions, and precise placement plus matched dosing gives agronomists a tool to reserve chemistry for the weeds that need it. Whether that translates into a full programme change depends on the weed spectrum, the crop and the cost structure of each farm.

Why dose control follows detection

The sequence of the upgrade follows a clear technical logic. Detection alone lets a sprayer skip the clean hectares between weeds. Dose control lets it discriminate among the weeds it does find. Together, the two functions push application decisions down from the field scale to the individual plant, which is where herbicide performance and cost are ultimately decided.

John Deere has positioned See & Spray as a pillar of its broader precision agriculture portfolio, and this addition signals continued investment in the platform rather than a one-off refinement. Rival manufacturers are pursuing comparable camera-guided spraying routes, so buyers should expect the competition between detection systems to extend into dose control as the technology matures.

What should farmers watch next?

Growers should watch which crop and machine combinations receive the variable rate function first, and how John Deere prices and packages the capability for existing hardware versus new purchases. Trial results comparing variable rate passes against fixed-dose spot spraying will show whether the dose savings justify any added complexity in setup and calibration. Availability details and rollout timing for specific markets are the next announcements to monitor.