Barring fire or harvest, Oregon forests could double carbon storage capacity

Using our forests for carbon storage could cut back on greenhouse gas emissions.

Researchers at Oregon State University say that Pacific Northwest forests hold significant potential to increase carbon storage and help mitigate greenhouse gas emissions if they are managed primarily for that purpose through timber harvest reductions and increased rotation ages.

In the complete absence of stand-replacing disturbances - via fire or timber harvest - forests of Oregon and Northern California could theoretically almost double their carbon storage, the researchers concluded.

Although it's unrealistic to expect that trees won't be cut and fires won't occur, the research provides insight into how carbon storage capacity is influenced by forest biomass, age, climate, disturbances and soil fertility. If all forest stands in this region were allowed to increase in age by 50 years, for example, their potential to store atmospheric carbon would increase by 15 percent, the study concluded.

That would be a modest, but not insignificant offset to the nation's carbon budget, scientists say, since this region accounts for 14 percent of the live biomass in the entire United States.

The findings were made by scientists in the College of Forestry at Oregon State University, as the result of almost two decades of analysis of 15,000 inventory plots in a large region, through several different projects, as part of the North American Carbon Program. The scientists, who said they have often been asked what the theoretical potential was for storing carbon in these forests, conducted the analysis using inventory data that captured current variation in biomass due to many factors.

"We have known that forests in this region have high productivity, and in recent years we have learned they have a high potential to store large amounts of carbon even at very old ages," OSU forestry professor Beverly Law said in a university news release. "The forests west of the Cascade Range are also wetter and less likely to be lost to fire. We suspected these forests might provide more opportunity for carbon storage than has been recognized, and these data support that."