INDEPENDENCE, Ore. — How much water does a hazelnut tree need to produce the best crop?
Definitive answers are still in the future, but there’s hope in technology, and in the trials of other growers, said expert panelists at an April 4 talk that attracted dozens of farm managers, irrigators, engineers, students and would-be growers.
The answer to the question, had it been asked 50 years ago, would have been “none.” Hazelnuts have traditionally been grown as a dryland crop once they reach fruit-bearing age. Most mature trees are not now irrigated.
But several economic and environmental factors have changed the landscape of this tree that grows in the U.S. almost exclusively in Oregon’s Willamette Valley, according to panelists Nik Wiman, Oregon State University Extension hazelnut specialist; Dennis Carlson, irrigation manager for AgriCare; and Alan Campbell, president of SmartOrchards and SmarterAg.
The event was organized by Alex Paraskevas of the Strategic Economic Development Corporation.
Water shortages, new technology, Eastern Filbert Blight, the surge of new disease-resistant tree plantings, along with increased production and prices have challenged managers to rethink traditional methods of farming. Despite challenges, hazelnut acreage in Oregon has more than doubled in the past five years to 70,000 acres. As a result, production in 2018 climbed to 52,000 tons, compared to 31,000 in 2015.
The blight had threatened acreage five years ago — there were 30,000 acres in 2013 — but blight-resistant cultivars, and new growers, have expanded acreage to 45,000 productive acres, with nearly 30,000 more acres in young trees planted and due to come online in the next few years, according to industry officials.
Research into best growing practices for the new hazelnuts is superimposed onto a background of potential water shortages in Oregon. The shortages are dire enough to prompt the U.S. Army Corps of Engineers and the State of Oregon to review how the Willamette River’s water supply will be reallocated in the future to meet agricultural demands.
SEDCOR is sponsoring another free panel discussion on that subject at 7:30 a.m. April 18, at the NW Wine Studies Center in Salem. Register at SEDCOR.com.
Given new circumstances for a crop grown in the Willamette Valley for nearly 150 years, which methods are best for the new cultivars? Extension specialist Wiman said researchers are working on definitive answers. Wiman, Campbell and Carlson described new technology that aims to track an orchard’s water transport levels, from the root to air, in new and in mature orchards. New internet technology, developed in the past few years, can also transmit data from the orchard to collection centers nearly a mile away, making it less expensive to track orchard health, and possibly more accessible to smaller operations.
The panel discussed the virtues of solid-set overhead irrigation, which waters the entire orchard but uses more water. Most of the research now underway focuses on the more conservative drip irrigation: one type dampens the soil in a “V” pattern; another forms an onion-shape, and an experimental drip irrigation line is buried.
Meanwhile, the increased acreage has growers looking for answers now, not later. They may have found some help from vintners. Exacting winegrowers have long studied the precise impact of irrigation’s timing, amount and methods. Technology developed in the vineyard is now coming to Oregon’s hazelnut orchards.
In addition, California’s recent drought, which impacted the state’s thirsty but lucrative crop, almonds, may also teach hazelnut growers a thing or two about water conservation methods.
Campbell, a University of California-Davis plant physiologist who earned his chops working in Northwest and California vineyards and orchards, is now working with hazelnut researchers to bring irrigation methods gleaned from almond and winegrape growers.
No orchard is the same as the next, Campbell said. However, precise data and historical information can equip growers with possible solutions to production challenges, he said.
“We’re trying to help the industry figure that out,” said Campbell.
There are no quick answers, the panel agreed, although they were optimistic about early discoveries.
“We’re still years away from knowing how to effectively irrigate hazelnuts,” said Wiman. OSU’s research has focused on the irrigation needs of the new resistant hazelnuts. As data is collected over time, Wiman hopes researchers can help growers determine the irrigation balance that produces the best nuts possible with the least water.
Already, in orchards throughout the state, OSU and private researchers are planting state-of-the-art sensors, probes and towers to collect the details of growth that may save the crop that was once doomed by disease. Its next challenge, panelists agreed, will be impending water shortages.
“Having the data, over time, will help us make decisions,” said AgriCare's Carlson. The company he works for manages nearly 2,000 acres of hazelnuts.
Future decisions will depend on the information they gather.
“There’s not just one answer,” said Campbell. “Every farm is different.”