PATERSON - On a day-to-day basis, steam is used for a lot of things. It's used to steam clean carpets, iron clothes and now it's being used to rid vineyards of weeds.
Monday afternoon, approximately 20 area grape growers gathered at the Columbia Crest vineyard in Patterson to watch the Atarus Stinger, a propane-powered thermal weed control machine prototype, at work.
Jack Maljaars with VineTech Equipment in Prosser explained that the Stinger has been in use in Australia since 2000 and is just now being tested in the United States. He explained that the Stinger, which consists of a small, towable apparatus that includes a water tank, a propane tank and a single arm, works by creating steam that reaches temperatures of more than 800 degrees. The steam, which directed down, hits the weeds at the base of the grapevines and attacks leaves and stems, breaking down the cells and killing the weed. Maljaars noted that the Stinger is not a heavy piece of equipment and can be towed by most tractors and four-wheel drive vehicles.
Maljaars said depending on the weather, growers should begin to see the weeds they've gone over with the Stinger begin to die off almost immediately. He said after about 10 minutes you can begin to see the plants deteriorating.
Although results are almost immediate, Maljaars said it can take about a week to see the full results of the steamer.
Maljaars said the Stinger is a good option for grape growers who are looking to go organic. He noted that using steam to control weeds is environmentally friendly and can be a more cost effective way of dealing with weeds in an organic vineyard. He noted that currently some of the only ways to deal with weeds in an organic vineyard are to mow, till or hire people to weed by hand.
Maljaars said the problem with mowing and tilling is that it can often damage the root stalks of the grapes, while hand weeding can be costly.
Maljaars said this is the first year the Stinger has been brought in for use at the vineyard level in the United States. He noted that during the machine's test runs, especially those at Columbia Crest, the company has been looking at the machine's cost effectiveness, its durability and its serviceability.
Bill Dickard, assistant vineyard manager for Columbia Crest, said he has been testing the Stinger for about a month. He said he's used the machine on about 10 rows at the vineyard and can see where it has killed back the weeds.
When it comes to when is the best time to use the Stinger, Dickard said he's found that the younger a weed is when it's hit with the steam the better it dies back.
"Something like this is another option for weed control in our organic sustainable area," Dickard said, noting that about 18 percent of the grapes grown in the vineyard are organic.
Doug Walsh with the Washington State University agriculture extension office in Prosser noted that more and more grape growers are trying to go organic and that the steamer would be a good way to control weeds in organic vineyards.
Walsh explained that keeping weeds under control can be important in a vineyard because of the stringent water management that has to take place. He said weeds simply take away from the water that is being delivered to the grapes themselves.
"Weeds compete for water," Walsh said.
He added that one reason the Stinger works well in a vineyard is because most farmers water their grapes using drip irrigation. This makes it easy for a piece of machinery, like the Stinger, to easily pass over the floor of the vineyard and take care of the weeds. The same is not true in orchards, where many farmers are still using sprinkler irrigation.
Although the Stinger being tested in Paterson may not be ready for orchard work, Maljaars said it is something the company is looking at. He said the reason they are concentrating on vineyards right now is because there is a movement to go organic in the grape business.