The introduction of Roundup Ready crops did not bode well for weeds – or for WeedSeeker technology.

The herbicide application system, which uses optic sensors to automatically find and spot-spray weeds, was patented in 1994 by electronics engineer James Beck.

It was obviously a viable product at the time. In 1996, Beck sold his company, Patchen, to the John Deere Co., which intended to incorporate WeedSeeker into its sprayers.

Unfortunately for John Deere, that was also the year Monsanto introduced glyphosate-resistant, Roundup Ready soybeans.

The genetically modified seed allowed farmers to spray the herbicide over the top of the crop, killing the weeds but leaving the soybeans unharmed.

Within two years, Roundup Ready corn also was introduced.

In effect, farmers of these two major crops no longer had as much use for the hooded sprayers that applied herbicide between rows – or for an optic-sensing system that sought out weeds.

“That definitely slowed the use of WeedSeeker,” said Ted Mayfield, chief operating officer of NTech Industries, which owns the technology.

In 1998, John Deere sold Patchen to one of its regional dealerships, Rainbow Agricultural Services in Ukiah, Calif. The Mayfield family, which owns the dealership, began operating Patchen as an independent business and eventually renamed it NTech.

WeedSeeker’s streak of bad luck continued: The patent for Roundup expired in 2000. That allowed pesticide manufacturers to produce low-priced generic glyphosate, reducing the incentive for farmers to minimize their Roundup applications.

By that time, though, NTech was fundamentally retooling the technology.

Instead of being used to seek and destroy weeds, the optic sensors would measure crop’s health and immediately dispense the right dose of fertilizer.

NTech developed the new GreenSeeker technology jointly with Oklahoma State University, which had been researching how to measure crop vigor with red and near-infrared light since the 1990s.

With the WeedSeeker, the red and infrared light was used to distinguish weeds from bare ground. GreenSeeker essentially took the technology one step further: By monitoring the red and infrared light reflected from the plant, the system is able to calculate the plant’s nitrogen needs.

“Red light is absorbed by plant chlorophyll as an energy source during photosynthesis,” according to a GreenSeeker fact sheet. “Therefore, healthy plants absorb more red light and reflect larger amounts of (near-infrared light) than those that are unhealthy.”

Since the company launched GreenSeeker in 2001, it primarily has been used for nitrogen applications in corn and wheat.

“As fertilizer goes up (in price), we get more people interested, because it becomes more of a pain point for them,” Mayfield said.

The technology has turned out to be a lot more versatile, however.

Researchers are trying to adapt GreenSeeker to fungicide applications in vineyards and to measure crop health in barley, rice, potatoes and other crops.

Interestingly, NTech doesn’t actually fund the research. The company just sells GreenSeeker units to private companies and universities, which study how to reconfigure the technology.

The arrangement works well for everybody: NTech sells the tool, and researchers decide what to do with it, Mayfield said. That way, the potential uses for GreenSeeker are as varied as the agricultural industry.

“There are going to be applications developed that haven’t even been thought of,” he said.

For example, Travis Hillman, president of the AG-TECH company in The Dalles, is adjusting GreenSeeker to work in grass seed.

“The key is to produce the max yield with minimum fertilizer,” he said.

Meanwhile, the original WeedSeeker technology has seen a surge in popularity among Northwest wheat growers as glyphosate prices shot back up, Hillman said.

Dryland wheat farmers leave fields fallow every other year to let depleted moisture build up again. To do that, they must keep that land clear of weeds; WeedSeeker allows them to kill unwanted plants efficiently without spraying the entire field.

The technology can save up to 80 percent in late-season glyphosate use, Hillman said.

NTech has found other niche markets for WeedSeeker as well. For example, the technology is widely used by the U.S. military for spot-spraying weeds that pop out from cracks in concrete, Mayfield said.

“Nearly all U.S. bases have the WeedSeeker doing weed control,” he said.