Oregon Public Broadcasting

Friday is the last day that Oregonians  can weigh in on how the state should treat  businesses that emit greenhouse gases. But some environmentalists are worried that a key aspect of the carbon debate is getting short shrift: namely, what’s happening on forest land.

As Rob Manning reports, global warming is opening a new front in the decades-long battle over old growth forests and logging.

Environmentalists have been working on protecting old-growth trees for years. There are a lot of reasons for that. For one thing, healthy forests provide clean drinking water.

And they provide habitat for fish and wildlife, as well as for outdoor enthusiasts to explore the wild.

But according to a new report from the environmental group, Oregon Wild, old growth forests are vital for another reason: They absorb carbon dioxide, the most common greenhouse gas.

Jonathon Jelen with Oregon Wild says old growth forests in the Northwest  are particulary valuable.

Jonathon Jelen: “They can actually contain more carbon than any other ecosystem on earth per acre. We’ve got a pretty valuable resource in kind of Mother Nature’s natural defense toward global warming and I think it’s critical that we protect these areas.”

Jelen is looking up at an old Douglas Fir. He's guessing it's been around well over 200 years. We're in the Mount Hood National Forest, on land designated for possible timber cutting, under the Northwest Forest Plan.

Jelen, and his Oregon Wild colleague, Sean Stephens, say logging here would destroy the forest’s ability to store carbon.

Sean Stephens: “These big old trees -- they store carbon not just in this huge trunk and the branches up there, but they pump it down into the soil, and so all the structure down here is sucking in the carbon and storing it as well. So, if you cut the tree down, you can make wood products out of this, but then the slash burn, and all the soil disruption, that’s where all of it escapes from. You can’t rebuild that just by replanting, and having a new tree growing.”

But the industry group, American Forest Resources Council, takes issue with Oregon Wild’s findings.

President Tom Parton emphasizes that younger trees – rather than old ones – are the most efficient way to absorb carbon.

Tom Parton: “We think that as trees grow older, they lose their effective ability to sequester carbon. That’s why we think it’s a lot better to have a younger, more vibrant stand growing, that’s healthy, that sequesters carbon, and really put that into storage.”

Oregon Wild doesn’t dispute that young trees can store carbon more efficiently. But they say cutting old trees to make way for younger ones doesn’t make sense either, because cutting trees down also releases carbon.

The American Forest Resources Council has another major bone to pick with environmentalists.

Tom Parton says a whole lot of greenhouse gases are released when wildfires burn forests.

Tom Parton: “Last year, for example, we burnt up nearly ten million acres of wild forestland. Forest fires put about six tons of carbon dioxide per acre into the atmosphere. And that’s an incredible amount of greenhouse gases.”

But according to a study cited in the Oregon Wild report, logging adds more carbon to the atmosphere per acre than fires do.

Walking me through the Mt. Hood National Forest, Jonathon Jelen with Oregon Wild explains what happens when a forest is cut.

Jonathon Jelen: “It’ll lose about ten percent of the carbon once it burns. But most of the carbon will stay on that site. However, when you log it, you lose about fifty percent of that carbon pretty much immediately. And especially clear-cut areas can be sources of carbon for decades to come.”

Recent reports from researchers at Northwest universities tend to support  Oregon Wild’s arguments, though policy implications are hazy. But ultimately, the biggest question may be: are alternatives to forest products any better for the environment?

For example, Mark Harmon with Oregon State University says using steel and concrete to build homes may use even more carbon that cutting down trees.

Mark Harmon: “One of the problems is that, unlike a forest, where you can go and measure what’s there, or forest product use, which you can at least inventory houses and things like that, this is somewhat of, I’m not going to say it’s imaginary, it’s very abstract. You can’t really inventory what isn’t released.”

Oregon's Department of Environmental Quality has intentionally punted on this issue for its initial run at tracking carbon emissions. But there is a task force working on the forest policy for the multi-state effort to curb greenhouse gas emissions.

Of course, that’s not without controversy, either. Environmentalists say the members of that group come almost entirely from the timber industry.