When betting big on converting wood to biofuel, first make sure you have enough trees to do the job.

That's the lesson Michigan is learning as forestry experts question whether the state can grow enough timber to support what could be the nation's first cellulosic ethanol plant producing commercially viable biofuel from wood. Biofuel startup Mascoma plans to build the $225 million refinery near Sault Ste. Marie in Michigan's beautiful upper peninsula. It is working with Longyear, a Michigan timber company that owns at least 100,000 acres of forest in the western part of the state.

The million refinery would consume 375,000 cords of timber – a cord measures 8 feet long, 4 feet wide and 4 feet tall - to make 40 million gallons of cellulosic ethanol annually. Therein lies the problem.

Mascoma converts plant matter into ethanol using consolidated bioprocessing. The method uses microbes to combine four biological processes – cellulase production, cellulose hydrolysis, hexose fermentation, and pentose fermentation – into one. The company says it is faster and cheaper than gasification, which uses heat to produce ethanol, or more traditional methods that use chemical pretreatment and enzyme additives.

Mascoma has scooped up more than $100 million in venture capital. General Motors took an undisclosed equity stake in the company last year when it still had two dimes to rub together, and the state of Michigan – which signed a deal with Mascoma in June – has kicked in $23.5 million and said the state grows 2.5 times more wood annually than it harvests.

Maybe.

"It's a bogus statistic and they've been using it for years," Ann

Woiwode, head of the Michigan Sierra Club, told the Michigan Messenger. The only way that number can be even remotely close to reality, she and other critics believe, is if it includes wood growing on private land. An official at Michigan's Hiawatha National Forest (pictured) suggests feeding the Mascoma plant would wipe out the annual harvest in the eastern Hiawatha within 180 days. The Messenger also reports that a Louisiana Pacific plant that would be located down the road from Mascoma is worried there won't be enough wood to go around.

No one should be as anxious about this discrepancy as the people who run Michigan. Gov. Jennifer

Granholm has touted the Mascoma project as vital to the state's future. The Michigan Economic Development Corp. believes there is more than enough timber to go around, according to the Messenger.

Longyear executives claim they aren't worried and say several timber mills have closed in the past few years, opening up some 2 million acres of woodland that is no longer in demand.

Hopefully they can get what they need without deforesting the state.

Photo: Flickr / mtsn

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