CORVALLIS - A forest management technique that allows landowners to harvest their trees and have their forest, too, may be of considerable interest to many of the smaller, non-industrial landowners that Oregon now looks to for about 30 percent of the tim ber reaching its mills, experts say.
With implications for enhancing wildlife and scenery while providing both timber and economic return, a case-study of the selection thinning concept will be presented by Oregon State University researchers and practicing foresters at a special symposium on May 24 at the CH2M HILL Alumni Center on the OSU campus. It is open to the public.
Computer simulations indicate this management approach on a long-term basis might provide as much as 90 percent of the wood production as a more conventional approach that includes a clearcut on a 50-year rotation, foresters say. And at any given time it leaves a largely intact, healthy forest.
But there are some economic and management tradeoffs that make this "modified selection thinning" approach impractical to use for large companies trying to survive in a global timber market, said Bill Emmingham, an Extension silviculture specialist in th e OSU Department of Forest Science.
"This type of selection thinning could be of particular interest to landowners who want to retain a somewhat diverse forest all the time, but still get a periodic return from timber sales," Emmingham said. "In Oregon, that might describe a lot of people. About 16 percent of our forest land providing nearly 30 percent of the timber to Oregon mills is now managed by about 50,000 non-industrial private owners."
Many of these properties are small, with only 10-20 acres including a home site, and owners are reluctant to clearcut their backyard, Emmingham said.
And one of those forests - the 250-acre Brown Tract on the western edge of the Oregon Coast Range - was the recent subject of an OSU case study by graduate student Darin Stringer, and will be the featured topic of the upcoming symposium. This land has be en managed with an approach that avoided clearcutting, used mostly natural regeneration and about every four years was "thinned" to harvest some of the largest trees.
With that somewhat non-traditional approach, this land produced 5.6 million board feet of mostly Douglas-fir timber during the past 35 years and remains about 80 percent forested with a mixture of Douglas-fir, grand fir and bigleaf maple trees. Recently, some very large or "legacy" trees have been left to further develop the land's ecological diversity.
Computer simulations with the Organon growth model suggests that over a 100-year period, this approach would produce 91 percent of the board feet volume, including that harvested and left standing, as conventional clearcutting and replanting of Douglas-fi r.
On average it left triple the standing timber volume and produced almost triple the volume of logs greater that 16 inches in scaling diameter.
There are several potential advantages to this approach, Emmingham said. It could be used to retain the appearance of a growing forest in perpetuity, and provide wildlife diversity with some "late-successional" or old-growth characteristics. The economic return would be more regular and some timber could be harvested virtually anytime.
The disadvantages, he said, might include need for improved logger training, concerns about greater forest soil compaction, insufficient natural regeneration, and growth losses associated with increased numbers of hardwood trees or "legacy" trees. Most o f those issues could be addressed with careful forest management or training programs. But it's unlikely, Emmingham said, that this type of thinning would ever produce as much total economic return as conventional clearcut forestry because economic invest ments must produce high rates of return.
"It's important to understand forestry approaches such as these for people who choose to emphasize social or ecological goals, even if it doesn't optimize their economic return," Emmingham said. "But forest management that's truly sustainable for larger companies and even our nation as a whole also has to consider the economics, and this management approach can't provide the same return as the more conventional techniques."
Having conceded that, Emmingham said, the modified selection thinning approach might be a concept that suits the goals of many Oregon small landowners, because it provides periodic income and still makes a fair profit, but leaves a reasonably attractive forest at all times. And the tract being highlighted in this seminar has been "green certified" under the Smartwood Program and recently sold "green" certified logs.
The seminar will explore the development and history of this stand, the techniques used to manage it, the current timber inventory, economic issues, and allow for questions and discussion about sustainability. Titled "Sustainable Management of Family For ests: Selection Thinning on the Brown Tract," it will begin with registration at 1:15 p.m. and conclude at 5 p.m. There is a $15 fee to attend. More information can be obtained by calling (541) 737-2329, or registration can be made on the web.