As Midwest vineyards move in next door to longstanding fields of corn or soybeans, they don’t always make good neighbors. Occasionally, herbicides like 2,4-D drift beyond their target, and for nearby vineyards the results can be devastating.
2,4-D is a common herbicide used by farmers because it kills weeds but doesn’t kill their corn. Landscapers and golf courses use it on lawns and fairways. Highway crews often spray 2,4-D on road ditches.
“Unfortunately, it just so happens that grapes are very sensitive to small amounts of 2,4-D,” said Lowell Sandell, a weed scientist at the University of Nebraska Lincoln.
The problem is not direct spray, it’s herbicide drift. Drift can happen with any weed killer. A stiff breeze can carry tiny droplets from the sprayer in one field to the vineyard next door.
But 2,4-D and another chemical, dicamba, remain a threat for drift up to two days after they are sprayed. On a hot day they can volatilize, or evaporate, and take to the wind.
Tom Zumpfe has seen the results first hand. He and his partner, Cathleen Oslzly, planted 8,000 grapevines on their acreage near Eagle in eastern Nebraska as an ambitious retirement project.
“We put our first plants in the ground in 2006,” Zumpfe said, walking through vines of Frontenac, Seval and Vignoles. “Close to 16 acres. And we’re probably the fourth- or fifth-largest vineyard in the state.”
Their plan was to build their winery last year and officially open for business. As Zumpfe held a vine with pale, shriveled leaves, he explained why those plans are on hold.
“You see, this leaf looks like it’s had hot water poured on it,” Zumpfe said. “That’s 2,4-D signature type of damage.”
Last year, Zumpfe’s plants were hit with 2,4-D, leaving his vines with that same scalded look. It was one of 75 drift cases reported to the Nebraska Department of Agriculture in 2012. This year, it happened again. Zumpfe has lost two years of harvest.
“We thought we were going to lose about half our vineyard the plants looked so bad,” Zumpfe said. “We had about a $600,000 loss in sales.”
Grape and vegetable growers across the country are concerned drift could be an even greater threat to their farms in the future. Monsanto and Dow Agrosciences are developing soybeans that are resistant to either 2,4-D or dicamba in addition to the herbicide, Roundup. It’s a way of getting past Roundup-resistant weeds.
Along with the new seeds, there will be new formulations of 2,4-D and dicamba, which the companies have said will reduce drift.
“They will probably certainly be better, but any time you apply a pesticide there’s drift potential,” said Lowell Sandell at UNL. “That’s why folks want to take the most care they can.”
Nebraska grape growers are seeking extra reassurance. A bill in the Nebraska state legislature would have created buffer zones around vineyards where farmers would need permission before spraying 2,4-D or dicamba. That could make the new soybeans irrelevant. It was a big request from a small industry.
The bill stalled, but the agriculture committee is studying the drift issue this fall.
Jeff Wilmes, general manager of Kaup Seed and Fertilizer in West Point, Neb., thinks restrictions are unnecessary.
“If you’re a good neighbor with that vineyard, you’ll work around what’s the best time to spray,” Wilmes said.
Kaup Seed and Fertilizer does contract spraying in northeast Nebraska. Before spraying, they go to Drift Watch, a website where vineyards can map their fields. If a sensitive crop is close by, they call ahead and make sure the wind is blowing the right way.
But Wilmes said grape growers should also be aware of their surroundings. Nebraska’s 30 wineries cover a few hundred acres, while corn and soybeans cover millions.
“The agriculture was here first and so they need to have a little bit of an understanding that there will be some of these events happening and spraying and fertilizing, that whole process that goes along with production agriculture,” Wilmes said.
Drift seems to be a bigger problem right now for vineyards in states like Nebraska, South Dakota and Kansas where the wine industry is still in its early stages, according to Iowa State University grape specialist, Mike White.
After a rash of drift incidents in the early 2000s, White said Iowa is down to a few severe cases per year. He said the numbers went down with education, sometimes by workshop and sometimes by lawsuit. White said settlements can reach $20,000 per acre, and news like that travels fast.
“It’ goes through the coffee shop. It goes through the (grain) elevator,” White said. “It only takes about one settlement in a local area and then everybody says ‘Hey, we better not drift on that vineyard.’”
August should mark the beginning of harvest season at Dove Landing vineyard, but any grapes Tom Zumpfe finds on the vine are being dropped to the ground to allow the vines to reserve their energy.
With time they can work through the effects of drift. Zumpfe plans to do the same.
“We’re in it for the long haul,” Zumpfe said. “These plants, typically they’ll live 50, 75 years. They could be here for a long, long time. As long as we can keep them healthy, they will be.”
The 2,4-D and dicamba resistant soybeans are perhaps another two years away from federal approval. In the meantime, grape and vegetable growers in the Midwest will push regulators for tougher drift rules and ask their neighbors to look before they spray.