It caused the deaths of 750,000 people in Ireland in 1845 and drove thousands to flee the country.
Now, it’s migrated to the Columbia River Basin, where modern farmers are unleashing tanks of sulfuric acid, fungicides and expensive equipment to control the scariest outbreak they’ve ever seen of potato late blight.
“We allowed ourselves to think that it couldn’t happen,” said Robert Thornton, a potato expert at Washington State University. “We may have misjudged it.”
Late blight is a furious fungus that left unchecked can wipe out thousands of acres of potato plants in a week. It can dramatically cut a farmer’s yield at harvest, spawning spud shortages and higher prices.
The plant disease can’t directly hurt consumers, but it can put a dent in their pocketbooks.
The fungus already has helped boost the average price of packed baking potatoes by 130 percent in four months, according to the Federal-State Market News Service in Idaho Falls. Fewer total acres planted in the Northwest and a drought in Maine also have contributed.
On Wednesday, wholesale potatoes headed to restaurants and grocery stores sold for 30 cents a pound, up from 13 cents in May, Market News said. However, a check of Spokane supermarkets showed that price hikes have yet to reach consumers. Potatoes were offered in store promotions for as little as 10 cents a pound.
Inland Northwest farmers and processors know that won’t last. As the nation’s leading supplier of fresh and frozen french fry potatoes, they worry that late blight could cause a shortage of raw product needed to fulfill orders from McDonald’s, Burger King and other fast-food chains.
“It could be a real scary winter here,” said Tony Czebotar, who owns 4,000 acres of potatoes from Odessa to Pasco.
Washington farmers, who will begin digging up their fall crop next week, have 147,000 acres in potatoes. Idaho has 400,000 acres, mostly in the southern half of the state.
Irish potato farmers 150 years ago had no way to control late blight. In two years, the disease caused widespread famine, starvation and death.
With better shipping routes, food stockpiles and the invention of pesticides, such devastation no longer is a threat.
But the fungus can still cause economic ills for farmers.
Late blight has forced potato farmers this year to spend $50 to $200 per acre to control the disease and keep it from contaminating tons of spuds held in long storage sheds. The sheds keep potatoes fresh through the winter for french fry processors.
“I’ve never seen anything like this,” Czebotar said. “We’ve been applying fungicide every six days. Our costs have skyrocketed.”
Some processors also are requiring growers to use sulfuric acid or other defoliants prior to harvest to destroy vines where late blight feeds. This costly practice reduces the chance that the disease will be carried into storage sheds or reappear during the 1996 planting season.
Thornton, a Cooperative Extension horticulturist, recommends that farmers store potatoes dry, without humidifiers blowing in moisture. That should retard the occurrences of late blight-induced rot.
Late blight surfaces periodically in the Columbia Basin. But not until 1991 did a mutated form of the disease show up to stay.
Thornton attributed the outbreak to a new strain of the disease, which resist pesticides, and wet conditions caused by pivot irrigation.