Threat to the Douglas Fir

Could disease take them? If so, what can be done to stop it?

By Thomas G. Dolan

Is there an imminent danger to the Douglas fir in the Pacific Northwest of being decimated by an unknown insect or fungi? If so, is there any hope of stopping this pestilence before it occurs? The short answer to both of these questions is yes.

Yesterday’s Devastation "People tend to think forests can last forever, and can be threatened only by fires," says Jerry Rust, secretary, Willamette Institute Of Biological Control of Monroe, Ore. "But this is not the case." He points to two important sources of eastern hardwood wiped out in the early 1900s. One was the American chestnut, literally an American symbol, written about by Longfellow, and destroyed by the import of a Chinese variety of chestnut which arrived carrying a fungus. The second was the American elm, eliminated by Dutch elm disease which came through Europe but also had its origins in China.

Today’s Threat That's history. Breaking news is what’s currently happening in northern California. It started a few years ago with a plague affecting the oak, called Sudden Oak Death Syndrome (SOD). "What they thought was attacking just oak trees has been spreading into the redwood forests and Douglas fir," Rust says. "For the better part of the past year it's been heading north. Officials are very alarmed." Rust says that he does not want to sound alarmist, but if the pestilence continues unabated, the results for the Pacific Northwest could be "catastrophic." It's easy to see why. In terms of the timber industry, nearly 4.7 billion board feet, about 70 percent of all the trees harvested in Washington and Oregon, are Douglas fir. But the impact would go far beyond the timber industry. The Northwest's forests are made up of about 85 percent firs, which gives the region its special character. Take them away and with them go outdoor recreation and tourism, and all the economic ventures that feed off of the forests, not to mention the many other species that depend upon them such as wild salmon. The major problem, Rust says, is that nobody knows what is causing the current disease.

Past Answers But there is hope. Recent history has shown how a potentially devastating plague can be stopped. A similar threat was faced in the 1980s with the gypsy moth. This moth decimated particularly broad leaf trees such as maples and oaks, but never got to the firs because a cure was discovered in the form of Bacillus thuringiensis (Bt), a relatively environmentally- benign toxin targeted right at the moth. The bacteria hatches in the gut of the caterpillar at the larvae stage and then explodes. Although there continue to be small outbreaks, this pest is carefully monitored by the departments of agriculture in three western states, so whenever a sign is detected, the area is sprayed and the threat goes away. At the time Rust was a Lane County commissioner, and on the Oregon governor's task force to deal with the gypsy moth. Rust explains that being involved in this process of detecting a pest, finding the solution, and then monitoring it "caught the imagination" of University of Oregon, Corvallis agricultural professors Dr. Bill Dennison, a plant specialist, and Dr. Jeff Miller, a specialist in butterflies and moths, along with a couple of technical writers, George Forester and Evelyn Lee. In 1985 they formed the Institute of Biological Control, which continues to monitor the gypsy moth and has been involved in other projects as well.

Future Hope Their current project deals with the issue at hand. They are sending 1,000 Douglas fir seeds to northeastern China to document what foreign pests, if any, are attracted to the trees as they grow. With no government backing as of yet, the Institute using its own funds has contracted with a company in Shandong Province, China called Yantai Taxus. The company specializes in growing yew trees in the search of a potential cancer cure. In China, ten separate lots in 10 separate areas will each grow one hundred firs. "We want to know what is out there and once we know something is indeed eating the firs, we want to see what it is to modify it and prevent it from coming here," says Rust. China is a potential source of infection because of the history of the chestnut and elm trees, and because there is not much in the way of controls over logs being imported. "Bugs can come in on the barge, on the stems, in the sawdust and any number of a variety of ways," says Rust. If infections are found in China it’s not necessarily bad news, as it eliminates one large area of worry. The Institute plans similar future testing in Asia for Ponderosa Pine and Western Red Cedars, and plans someday to go into Eastern Russia and Siberia where there are vast forests of Western Larch. In this country the Larch is found primarily east of the mountains in California and Oregon. Rust says that it will take five to 10 years before the results of the China experiment are known and, moreover, this project was conceived before the alarming news of SOD spreading to northern California redwoods and firs.

Taking Action What should be done now? "There should be multiagency task forces with ongoing efforts from the State and Federal departments of agriculture, with plenty of help from the private sector," Rust says. The timber industry can help by raising the level of public awareness. "Put some heat on the politicians we've elected, go to Congress and get task forces started," Rust suggests. "So far the pestilence is moving our way silently, without a lot of fanfare. If it really does explode, it will have our attention. But it would be better not to wait until then."

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