LINDA WERTHEIMER, HOST:
Here in the U.S., farmers in the Pacific Northwest are fighting for the survival of a unique crop. Oregon is where nearly all this country's hazelnuts - also known as filberts - are grown. They're an $80 million crop for the state. But farmers have been losing their trees to persistent fungus.
From Oregon's Willamette Valley, Deena Prichep reports on efforts to combat the blight.
DEENA PRICHEP, BYLINE: Rich Birkemeier farms a few hundred acres of hazelnut trees out in Canby, Oregon. And it was one of the first farms to be struck with Eastern Filbert Blight. That's a fungus that kills hazelnut trees - and almost killed Oregon's hazelnut business.
RICH BIRKEMEIER: A blighted tree will have this sunken tissue here, where you can see the inside. It is dead. As soon as it sets a heavy crop of nuts, it will split in half.
PRICHEP: Birkemeier is still pulling up dead trees.
(SOUNDBITE OF PUMP OF TRACK HOE PULLING OUT STUMPS)
PRICHEP: Fifteen hundred this winter. But a couple decades ago, he pulled up nearly all his trees. Even when you prune out the cankers, and spray the trees, they still get blight.
Birkemeier's wife Nancy does the farm's books.
NANCY BIRKEMEIER: Well, it was difficult. I mean we sold land, we cut timber, we didn't take a paycheck for about five years, you know.
PRICHEP: It got to a breaking point.
BIRKEMEIER: And I thought to myself, this is not sustainable. I'm never going to have big trees here again. And Dr. Shawn Mehlenbacher, he walked up to me and handed me his business card.
DR. SHAWN MEHLENBACHER: I came to Oregon State University in September 1986.
PRICHEP: Shawn Mehlenbacher is a professor of horticulture.
MEHLENBACHER: And one month after my arrival, Eastern Filbert Blight was found in Clackamas County.
PRICHEP: Mehlenbacher's breeding program has spent years on the best hope for the industry: blight-resistant trees. They discovered a naturally-occurring gene for resistance, and have been trying to breed it into good-producing, good-tasting hazelnuts. It's a slow process.
MEHLENBACHER: Waiting, waiting, waiting.
MEHLENBACHER: We operate on an eight year cycle - that's eight years from seed to seed.
PRICHEP: That means Mehlenbacher cross-pollinates two trees, then waits eight years for the next cross. And then another eight years. Even when he tests the trees by exposing them to blight, he has to wait 16 months to see if they get the disease. But the years of work have yielded trees that don't get blight at all.
(SOUNDBITE OF CROWD CHATTER)
PRICHEP: At this year's annual nut growers meeting, Mehlenbacher released the latest blight-resistant variety to about 500 eager farmers, processors, and chocolate-makers. But change doesn't come overnight on a tree farm.
TANNER KOENIG: Those new trees, it's year seven before you make any money on them. So you want to leave the big trees in as long as you can, but you got to take them out and replace 'em at some point.
PRICHEP: Twenty-seven-year-old Tanner Koenig pretty much grew up with blight. He's learned how to manage it, extending the amount of time one of the old trees can survive. And managing comes at a cost.
KOENIG: It's a constant battle. I have four guys that prune every day from the first of November until the end of March. It takes two guys to stack up all the branches all winter long. And then they spray about four times for it in the springtime.
PRICHEP: Other farmers, like Rich Birkemeier out in Canby, have abandoned spraying entirely. He's just taking down trees as they succumb to blight, and planting the resistant ones in their place
BIRKEMEIER: Now frankly, I like working with trees. And now, that we have come through the dark days of Eastern Filbert Blight, the farm is actually doing better every year. Partly because of the new trees, and partly because the market for hazelnuts right now is just very, very good.
PRICHEP: And because of the health of the market - and the health of the trees -Birkemeier hopes Oregon farms will keep consumers in Nutella and hazelnut lattes for generations to come.
For NPR News, I'm Deena Prichep.