The following story was written by a University of Missouri student as part of the 2011 Sonja Hillgren/Farm Journal Ag Journalism Field Reporting Institute. Learn more.
By John McLaughlin
SALEM, Mo.—A musty coat of sawdust smothered the sawmill’s rafters. Below, a lone mechanical arm helped guide fresh logs against the saw with robotic precision.
Horizontal cuts first scored the log’s side. A vertical cut followed, resulting in a rough two-by-four and scraps dropping to the conveyor for sorting.
Nearby, a large chipper noisily mangled the scraps into animal bedding, mulch and more sawdust, which hovered in the air even outside of Spencer Lumber — a 100-year-old sawmill near Salem.
In 2010, "they talked about putting in a biomass burner here," said Stephen Spencer, owner of the mill.
"We voted it down," he said. "It was going to destroy the forest."
Depending on how trees are harvested, renewable energy production using woody resources could threaten Missouri’s forests, forestry experts said recently. With the state’s lack of binding forestry regulations, attention has focused on whether loggers will participate in sustainable forestry while harvesting small trees and scrap branches for biomass burners, like one opening soon at the University of Missouri-Columbia.
"If there is more of a market, it pays to load the small trees," said Hank Dorst, of the Mark Twain Forest Watchers.
Rose-Marie Muzika, forestry chair and professor at MU said, "It takes a long time to develop a forest and to manage that forest in a way that makes it sustainable."
"And for most forests, sustainability means not removing everything at the same time," she said.
Pioneer Forest, near Salem, has more than a half-century history of sustainable timber management while making a profit. Missouri conservationist Leo Drey bought the first track of Pioneer in 1951. And loggers at Pioneer maintain single-tree harvesting techniques and best management practices while felling the forest’s timber.
Pioneer boasts a growth rate of double the statewide average for upland oak-hickory forests, said Peter Becker, a research coordinator for the Eastern Ozarks Forestry Council. Pioneer’s forests also have 80 percent more volume per acre, he said.
At Pioneer, J&G Logging — the forest’s current contractor — quickens natural processes and ends up with logs. J&G voluntarily minimizes a harvest’s impact on the forest.
When choosing individual trees, staffers at Pioneer look first at quality: a treetop with full leaf cover and branches reaching to the sky.
Mortality is considered. Small branches along the side of a tree imply stress. Loggers decide if the tree could survive until the next harvest, about 20 years later.
Tree spacing is important, as less-desirable trees invading the space of healthier trees are removed.
Pioneer loggers skid felled trees to limit damage to surrounding growth and avoid excessive soil compaction.
Ladders of low soil mounds, or water bars, span steeper log trails to divert water flow and lessen soil erosion, which silts creeks and rivers.
And timber is felled in a specific direction to avoid excessive damage to surrounding trees.
As for woody biomass energy, Pioneer staffers don’t believe their forest could support a new energy market based on woody resources.
"It is because (Pioneer) fears, based on experience and historical events, that people will abuse the process," Becker said. "Pioneer expresses concerns about new bio-energy markets that might result in excessive harvesting or over-harvesting."
The Eastern Ozarks Forestry Council and its partners found that about 20 tons of small wood per acre could be sustainably co-harvested with logs from well-stocked forests. This large amount of small wood could be used in existing lumber markets or for bio-energy, Becker said.
"In this scheme, it is forest management first, bio-energy second," he said.
At Columbia, MU adopted standards to ensure sustainable harvest of woody biomass for its power plant’s biomass burner. According to the university’s contract, standards require loggers to:
- Follow a written resource management plan approved by a forester recognized by the Society of American Foresters.
- Harvest timber via the Missouri Department of Conservation’s best management practices.
- Include at least one person per logging team who has completed harvesting training from the Missouri Forest Products Association, or an equivalent program.
- Not use clear-cut timber unless deemed necessary by certain conditions and approved by the site’s professional forester.
- Document the harvest site’s description, the owner’s contact information, harvest dates, amounts removed and a signed statement from the site’s professional forester attesting that sustainable harvest standards were followed.
The contract notes the university can hire an independent certified forester to inspect whether contractors keep to the plan.