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One of Idaho’s industries hardest hit by the recent housing boom and bust is forest products.According to the U.S. Forest Service, the timber harvest from Idaho national forests dropped from 172 million board feet in 1999 to 121.2 million board feet in 2008.The Idaho Division of Financial Management’s 2011 economic forecast reported there are about half as many mills in the inland region as there were 20 years ago.Still, the report projects growth in the industry over the next few years.“Idaho lumber and wood products employment hit a trough of 5,700 jobs in 2010 which was about 40 percent below its 2006 peak of 10,000 jobs. It’s projected to grow each year of the forecast, but it’s not fast enough to top the previous peak.” - DFMThe Division of Financial Management believes an increase in housing starts will help fuel a mild recovery in wood production.

Logging Leftovers Could Keep Invasive Species Out

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USDA

A new study from the research arm of the Forest Service suggests that leaving behind broken branches and the tips of treetops after logging can help fight invasive species.

Scientists suspected that fir boughs and other logging leftovers could act like gardener’s mulch and protect the soil.

Tim Harrington is with the Pacific Northwest Research Station. He’s part of a group that looks at the long term effects of logging. Harrington set up an experiment growing Doug fir seedlings under different amounts of cover. He found that young firs grew best when about half of the soil was covered with old branches.

“It’s kind of like a no-till system," he says. "Basically, do not the disturb the soil any more than you have to, and you will benefit the native vegetation. And you’ll also retain growing space for the seedlings of conifers that we’re trying to grow.”

Harrington says the woody cap over the soil helped trap plant nutrients like carbon and nitrogen.
And it protected the site from invasive species that often blow in on the wind and take over clear-cuts.

“Scotch broom, we found early in the study, that it was inhibited," he says. "Hairy cats ear, which is actually like a dandelion species, they’re just not coming in because they don’t have the exposed mineral soil to colonize.”

So, could leaving behind slash help provide an alternative to spraying herbicides on clear-cuts to control weeds? That depends a little on your perspective.

“I think the slash retention is potentially a helpful thing," says Scott Holub, a research scientist with Weyerhaeuser.

He says Harrington’s results showed that the native firs grew the most when slash and herbicides were used together to knock back weeds.

“Really the big driver we find is the weeds and when there’s more weeds there’s less tree growth,” Holub says.

Holob says Weyerhaeuser is conducting its own experiments to figure out whether leaving behind branches and needles after logging will keep the soil healthier in the long run.

Copyright 2013 EarthFix