Jeff Pollard inspected a Turkish fir seedling on his tree farm in Bakersville, N.C. He has grown Fraser fir for nearly 40 years, but a root-rotting mold has him looking to the Turkish species to save his business.

Allen G. Breed • Associated Press,

An unwelcome surprise under the Christmas tree: root rot

  • Article by: ALLEN G. BREED Associated Press
  • December 2, 2013 - 8:59 PM

– Jeff Pollard trudged up the steep slope and stopped at a desiccated, rust-brown tree. Two months earlier, workers had tagged this Fraser fir as ready for market.

It was going to be someone’s Christmas tree. And now it was dead. The culprit: Phytophthora root rot, a water mold that, once in the soil, makes it unfit for production.

Pollard has been growing Fraser fir in these western North Carolina mountains for nearly 40 years. To him, it’s “the ultimate tree.”

But this persistent problem has him looking to a species from the birthplace of old St. Nicholas himself for a possible alternative. And he’s not alone.

Growers in Oregon have been experimenting with the Turkish fir for more than 30 years. That species and the Nordmann fir, also native to Eurasia, have shown promising resistance to root rot.

“Phytophthora is a problem in most areas where true firs … are grown,” said Gary A. Chastagner, a plant pathologist and extension specialist at Washington State University. “It’s a national problem.”

Oregon leads the nation in Christmas tree production, with nearly 7 million harvested in 2007, the latest figures available from the National Christmas Tree Association. North Carolina was second, with 3.1 million.

One study estimated the potential losses to Oregon’s nursery and Christmas tree industries of up to $304 million a year if Phytophthora is not properly contained. Douglas and Noble fir are the dominant holiday tree species in the Pacific Northwest.

In North Carolina, it costs farmers up to $6 million a year, said John Frampton, a Christmas tree geneticist at North Carolina State University in Raleigh.

To date, no fungicide has proved effective to control Phytophthora on Christmas tree plantations. So once it’s in the soil, that’s it.

With hurricanes came rot

Pollard, who grows about 130,000 trees on several western North Carolina farms, said Phytophthora set in after Hurricane Fran in 1996 and got worse after 2004’s Hurricane Ivan. He’s lost about a quarter of his trees over the past six seasons, and the state rated the mortality on some of his stands at up to 80 percent.

Researchers at Washington State and several other universities are hoping to unlock the secrets to some species’ rot resistance.

In a greenhouse on the campus of NC State, master’s student Will Kohlway looked over rows of fir seedlings that had been inoculated with Phytophthora. He’s looking for genes related to disease resistance in Turkish fir. “Possibly we can speed up the hybridization and get something to the growers faster,” he said.

But what works in North Carolina might not necessarily help in the Northwest, where other species of Phytophthora are more common, Chastagner said.

Katie McKeever, a Ph.D. candidate in Chastagner’s lab, is working under a U.S. Department of Agriculture grant to create a nationwide collection of Phytophthoras from Christmas trees to understand regional variation in pathogen populations. But until native trees can be modified to have greater resistance, Pollard and others are looking toward other species.

Since 2004, Oregon growers have planted an average of 500,000 Nordmann and Turkish firs per year, with similar activity in western Washington and the Inland Empire, Chastagner said.

Pollard planted his first Turkish fir seedlings about six years ago and sold his first trees last year. He said his customers were “tickled to death.”

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