Please update your Flash Player to view content.

More News on OutdoorWire

OutdoorWire

OutdoorWire

Portal page for OutdoorWire Access and Landuse Central Read More
4x4Voice

4x4Voice

California off road recreation news and information Read More
MUIRNet News

MUIRNet News

News and information about issues affecting outdoor recreation Read More
4x4Wire

4x4Wire

Off road recreation and 4x4 Technical news and information Read More
TrailTalk

TrailTalk

4x4Wire TrailTalk Forums for a variety of 4x4 tech information Read More
  • 1

Retaining moderate levels of ‘slash’ linked to increased early growth in seedlings

OLYMPIA, Wash. Mar. 11, 2013. The downed limbs and other woody debris that are inevitable byproducts of timber harvest could be among the most important components of post-harvest landscapes, according to a new study led by the U.S. Forest Service’s Pacific Northwest Research Station.

Researchers found that retaining moderate levels of logging debris, also known as “slash,” helped to both directly and indirectly increase the growth rate of Douglas-fir seedlings replanted after harvest. The findings, which are among the first to speak to the benefits of second-growth logging debris, are published online in the journal Forest Ecology and Management.

“At levels typically left after forest harvesting, where 40 percent of the ground is covered by logging debris, we found that debris inhibited the growth of competing herbaceous vegetation and so preserved soil water,” said Tim Harrington, a research forester with the station and the study’s lead. “This means that just leaving typical levels of debris in place after forest harvesting helps new Douglas-fir seedlings to become established.”

The findings are based on a study of seedling development under three levels of logging debris—0, 40, and 80 percent cover—at two sites in Washington and Oregon affiliated with the North American Long-Term Soil Productivity study, a collaborative program launched by Forest Service Research and Development more than two decades ago. Harrington and his colleagues expanded on previous research on logging debris effects by increasing the number of seedlings studied, extending the study period to four years, and looking at the responses of additional variables, like vegetation abundance and seedling water potential.

In addition to having a “vegetation control” effect, the retained woody debris helped promote Douglas-fir seedling growth by reducing evaporation; slowing decomposition and allowing soil carbon and other nutrients to accumulate; and inhibiting the invasion of aggressive, non-native species, including Scotch broom and hairy cat’s ear.

These responses occurred where no herbicide treatments were applied. However, where the use of herbicides to control competing vegetation was combined with logging debris, seedling growth rates were the highest observed in the study, especially where debris cover was 80 percent.

“Industrial forest managers and private landowners in Washington and Oregon are already using early results of the study to prevent Scotch broom invasions,” Harrington said. “But these new findings suggest that long-term forest productivity will benefit from debris retention, indicating much broader applicability of the research,” Harrington said.

The study was conducted in collaboration with Robert Slesak, University of Minnesota; and Stephen Schoenholtz, Virginia Tech. It will appear in print in a forthcoming issue of the journal.

The Pacific Northwest Research Station—headquartered in Portland, Ore.—generates and communicates scientific knowledge that helps people make informed choices about natural resources and the environment. The station has 11 laboratories and centers located in Alaska, Oregon, and Washington and about 390 employees. Learn more online at http://www.fs.fed.us/pnw.

# # #

 

Share this --

FacebookTwitterDiggDeliciousStumbleuponTechnoratiLinkedinShare on Google+
Pin It

OutdoorWire Websites

OutdoorWire

OutdoorWire

Portal page for OutdoorWire Access and Landuse Central Read More
4x4Voice

4x4Voice

California off road recreation news and information Read More
MUIRNet News

MUIRNet News

News and information about issues affecting outdoor recreation Read More
4x4Wire

4x4Wire

Off road recreation and 4x4 Technical news and information Read More
TrailTalk

TrailTalk

4x4Wire TrailTalk Forums for a variety of 4x4 tech information Read More
  • 1

4x4 Tech from 4x4Wire

Jeep Tech

Jeep Tech

Jeep Tech from 4x4Wire Read More
Toyota Tech

Toyota Tech

Toyota Tech from 4x4Wire Read More
Mitsubishi Tech

Mitsubishi Tech

Mitsubishi Tech from 4x4Wire Read More
Isuzu Tech

Isuzu Tech

Isuzu Tech from 4x4Wire Read More
  • 1