Sudden Aspen Decline is a recent and unexplained phenomenon in which vast tracts of aspen forest in southwest Colorado and elsewhere in the Western U.S. are dying.
Forest officials hope that clearcutting the Wolverine parcels will stimulate root-based regeneration of the stands before the roots show too much deterioration.
“Investigations on the San Juan National Forest indicate that in stands experiencing sudden decline, aspen root systems are dying and that in some declining stands, few root suckers are being produced,” a USFS press release stated. “Because aspen regenerates primarily through root suckering, some managers and scientists feel that clearcutting before sudden decline advances too far is the best way to regenerate a new stand.”
“We’re afraid that if it’s allowed to go too long, then the more roots that die the less suckering we’ll get,” said USFS Forester Monica Ruiz-Diaz. “If we do nothing, we’re certain that the stand won’t regenerate. We’ve seen a couple of examples of that happening on the Plateau already.”
The project is of interest to numerous researchers, including insect and disease experts from the Gunnison office of the USFS Forest Health Management division, other foresters who are encountering the same situation in their districts, as well as researchers at Colorado State University. Scientists and land managers will study the project both before and after the cut to determine the effectiveness of clearcuts in halting forest losses associated with SAD.
The Uncompahgre Plateau has been logged extensively in the past and continues to be the site of ongoing operations. Ironically, some of these regenerated cuts are healthier than the remaining mature forest. Mark Schofield, Public Lands Coordinator for Western Colorado Congress, visited the site with forest officials last October.
“We visited two different sites,” Schofield recalled. “Adjacent to the first site was a stand that had been part of a timber sale a couple of decades ago. It had 15 to 20-year-old aspen trees that were in pretty good shape,” he said.
Schofield said that unlike other forest types in the region such as spruce-fir forests, clearcut aspen groves can regenerate, and that clearcutting is actually the preferred practice for aspen cuts. However, not all aspen clearcuts do regenerate, he said.
“In the past WCC has weighed in on some aspen cuts that have regenerated well, but there are also others that didn’t,” he said. “Some of that may have been because of scale. That was back when Louisiana Pacific [lumber mill in Delta] was open and there were vast aspen clearcuts.”
The WCC Public Lands Committee met on Wednesday, Jan. 16 to discuss the sale and to determine their official position. The announcement was not available as of press time.
“One thing we’re looking at is whether or not the sale is an appropriate scale, and there are other considerations to be taken into account such as sensitive wildlife habitat.”
Local retired forester Phil Miller has other concerns about aspen regeneration, citing impacts to aspen seedlings by cattle grazing and elk browsing. Miller will give a presentation on this topic at a CSU seminar on SAD.
“It’s a pretty serious problem. When you consider a place like Aldasoro where the elk use is so heavy, there’s no regeneration at all,” Miller said. “The overstory is over 100 years old, but there’s no regeneration.” Aspen is a short-lived species, and without ongoing seedling production, there will be eventual forest loss. “When those overstories die, there’s not going to be any forest,” he said.
At least part of the Wolverine parcel is leased for grazing, but officials have designed the project to mitigate the effects on regeneration. Foresters will fence Unit 29, which shows the most advanced signs of decline, with a 3-D electric fence system, and will create monitoring exclosures in the other four parcels in order to monitor the effects of browsing by cattle and wildlife. The 3-D fence consists of a baited single-strand outer perimeter, with a second inner perimeter of two strands of wire.
“You know what I think of electric fences,” Miller said. He cited the Big Burn tract west of Norwood, where foresters have erected electric fences to keep animals away from the seedlings. “They’re so flimsy you have to get someone out there to check them every day,” he said. Miller allowed that he’d never heard of the 3-D system to be used on the Wolverine Tract. “Maybe that’s effective,” he said.
Diaz-Ruiz considers the project urgent. “If treatment doesn’t take place in a short time frame on these units, we may not be able to regenerate them,” she said.
The USFS plans to issue a decision on the project by this spring, with work commencing in the summer of 2008.
Email comments to email@example.com, with “Wolverine Timber Sale” in the subject line. Mail or deliver written comments to GMUG National Forests, Wolverine Timber Sale Environmental Assessment, attn: Monica Ruiz-Diaz, 2505 South Townsend, Montrose, CO 81401. For more information or to comment by phone call Ruiz-Diaz at 970/240-5406. Comments must be received by Feb. 12, 2008.