A successful trial SenseApply uses a cab-mounted camera to detect weeds and assess plant health in real time as the sprayer passes through the field. The operator sets the parameters in advance for how much herbicide, nitrogen or fungicide to apply. The system offers farmers the greatest benefit where field conditions vary and traditional uniform spraying means some areas are over- or under-treated. For CNH, the DeRuwes’ farm offered the perfect testing ground because of its large area and hilly terrain.

For the DeRuwes, it was a chance to “play with different settings in terms of what rates we were going to use and what would work best for us, not to mention what the limits of the system were,” says Remie.

Last year, they found that in their first pass with the sprayer, fields had around 90% coverage of weeds. On the second spray, Jacob used the system’s ability to spray a uniform base layer and target bigger weeds with a higher dose, so that by the time they got to the third and final spray, the weed coverage was down to as low as 5% and typically around 10%.

“We reallocated our resources where they needed to go and it was doing a better job,” says Remie. The green-on-brown technology, which ‘sees’ weeds in fallow fields meant on a farm the size of the DeRuwes’, “You’ll drive for acres and you may not spray anything,” he added. "Chemicals are about ten to twelve dollars an acre. When you have 17 thousand acres to spray, you can do the math. We just didn't apply a lot of chemicals when we didn't need to, and we saved some money."

The technology also saved time and labor. Typically, a water tender truck would accompany the sprayer to refill it every 45 minutes to an hour. But Remie explained that “when Jacob leaves with the 1,700 gallons of water, he doesn’t always know how many hours it’s going to be before he needs to refill. With SenseApply we don’t need another guy tied up tending his sprayer,” says Remie.

Man and machine working together Although SenseApply is an automated system, it needs the operator’s knowledge and expertise to perform at its best. As the camera works by using vegetation spectral reflectance, or the amount of reflected light from plants, to identify them or assess their health, one consideration is the angle of the sun, says Jacob.

“In the early morning, the sun’s not up in the sky, it’s right in front of you sometimes. And if you’re going up and down hills, at noon the sun might be directly in front of you,” says Jacob. “Those are the kinds of things you have to think about. Am I going to spray this way or turn around and do it the other way and make sure the system is being more effective? You learn how to run the field a little differently, and it’s easy to do, but it’s something to think about each time.”

Compared with the earliest version of SenseApply they tested, the user experience is much improved in the model that is now ready to go on the market in North America. “It’s much more user-friendly, it’s easier to find the tools and apply the chemicals more efficiently,” says Jacob.