Restore Fire-Resistant Longleaf Pines, Get Clean Energy

Longleaf pine forest

One way to beat the large fires scorching drought-stricken Florida: restore the state's native Longleaf pine forests. But large-scale restoration of these forests—in actuality open savannas characterized by widely spaced stands of Longleaf pine trees—would require the removal of any existing vegetation, including established trees. Would this be the environmental equivalent of robbing from Peter to pay Paul?

Jack Putz, a botany professor at the University of Florida (UF), asserts that fires have been so intense of late because of Florida's too-dense forests, filled with hardwoods such as laurel oaks, water oaks, and sweet gums. Because fire-suppression efforts have only encouraged the growth of these hardwoods, the native Longleaf pine that was common when Florida was first populated have largely disappeared. Only 3 percent remains of the original Longleaf pine ecosystem, which spanned more than 91 million acres across the southern United States.

The result: Fires raging out of control as dense stands of hardwoods and pines burn intensely all the way to to their crowns. Widely spaced stands of Longleaf pines, on the other hand, burn slowly, with low fires that creep along the grass and brush at one- to three-year intervals. Y'know, slow hand, easy touch, and all that.While Florida foresters have been actively restoring Longleaf pine forests in small selected areas throughout the Southeast for a while, the catch is that the removal of a site's hardwood trees is expensive, energy intensive, and polluting. Make that really polluting.

But Putz argues that felled hardwood trees could be used as fuel to generate electricity.

In a press release from UF:

The hardwoods that invade after fire suppression could be burned in generators, a practice that already occurs at some sawmills, or converted to cellulose-based ethanol once that technology improves in the future. Such energy is "greenhouse gas neutral" because it emits no carbon from fossil sources.

Some landowners have taken to grinding up unwanted hardwoods into fuel chips, which are then burned, usually at sawmills, to generate electricity. This electricity is sometimes fed back into the grid when the sawmill is idle.

Putz and Brian Condon, a student in UF's food and resource economics department, analyzed 13 North Florida restoration projects producing such fuel chips with electricity generation in mind. They discovered that the amount of carbon harvested in the chips greatly outweighed what was consumed in the diesel used during harvest and transport. In other words, the process offsets carbon.

"People are looking for solutions and there are not many around, other than consuming less energy," Putz said. "But here's a solution to three problems: restoring our native Longleaf pine savannas, boosting clean energy and reducing fire risk." :: University of Florida

See also: :: L.A. Demands Fire-Fighting Goats

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