Increased growth rate should yield greater carbon uptake in New Hampshire forests
Could New Fast-Growing Tree Stop Climate Change?
CONCORD APRIL 1, 2012--Forest research scientists, working at a remote location on one of the Society for the Protection of New Hampshire Forests’ 170 permanently conserved forest reservations, have developed a fast-growing tree which could prove to be a breakthrough in the effort to reduce greenhouse gases that contribute to global warming.
Trees ‘sequester’ carbon well because of their volume of woody biomass and extensive root system. To enhance that process the forest researchers set out to develop a tree that grows extraordinarily fast.
The result is what they now label Pinus citius altius fortius, a sub-species of the common Easter White Pine (pinus strobus). And while early tests have shown that the new species can triple or even quadruple the annual carbon uptake of a standard White Pine, researchers also are quick to point out that it is not, as a few overly-exuberant members of a peer review team have claimed, a so-called ‘silver bullet’ for climate change.
How did they do it? The standard White Pine is monoecious, meaning that a single tree contains both the male strobili and female flowers that are required for pollinization and reproduction.
As one researcher said, “We just looked around at the world and couldn’t help but notice that in so many thriving life forms, the male strives to show off for the female, to prove he is the strongest and fastest of his ilk in hopes of impressing the female. So we applied that fundamental observation to the White Pine, made it dioecious instead of monoecious, and wow the growth rates just took off.”
Not Without Controversy
When word of the success of the experiments began to leak out, a number of rumors about the new species began to spread like pollen on the wind. Most of those rumors surround elements of the research that are not yet known—the ultimate lifespan of the tree and the decomposition rate, the suitability of the wood for traditional uses in construction and furniture.
“Since the program is less than a decade long we just don’t know about the longevity yet,” acknowledged Jack Savage, VP for Communications at the Forest Society. “For that matter we don’t even know how high they’ll grow—the tallest to date is now about 100 feet.
“However, the cell structure is similar enough to standard pinus strobus that there’s no reason to think the tree will die off more quickly. Similarly, we don’t yet know enough to know whether a dead tree decomposes faster than the regular White Pine.”
Carbon is released as trees decompose, so the rate of decomposition becomes a key measure of the potential for long-term carbon sequestration.
Other rumors include a fear that the new species does not have the same tensile strength of typical White Pine, which could cause a problem for builders. And some have suggested that the new species creates a lighter, fluffier sawdust that could cause problems in sawmills.
“The truth is that we haven’t even field-tested these pines in an enclosed sawmill,” said Savage. “There has been limited testing with a portable sawmill on the growing site, but those conditions are quite different from a typical commercial sawmill. The jury is out.
“What we do know, however, is that this sucker grows some fast,” Savage added.
Observers are astounded at the growth rates they are seeing with the new tree. Scientists asked to peer review the research have expressed a high degree of skepticism until they watch the tree grow themselves.
“You can literally watch one of the faster ones grow,” Savage said. “We’ve trained our ‘Tree Cam’ webcams on the things, only to have to aim the camera higher after a few hours.”
A standard White Pine will grow slowly at first, then accelerate after two to three years to as much as three feet annually from years 10-15. The new sub-species has been observed to begin rapid growth immediately upon being planted, and the male trees reach growth rates that are at times exponentially faster. The female trees are nearly as fast, presumably in order to compete for sunlight and soil nutrients.
Given the speed with which the newly-developed trees grow, there’s fun to be had as well. Last summer interns on the research team enjoyed “tree racing”—two interns would each pick a same-aged seedling and a planting site, plant simultaneously, then see which tree won the ‘race’ to a given height, say ten feet, at the end of the day.
“Some of these trees are really fast,” one intern who spent his summer planting the experimental trees told me. “I learned the hard way that once the roots hit the soil, I’d better jump back quick because sometimes they’d shoot up and knock me over.”
Told that story, Savage smiled and shook his head.
“That sounds like a bit of a stretch to me,” he said. “What we’ve learned though is that trees will do whatever they can to get attention, just as humans will say incredibly outlandish things just to get attention.”
The Society for the Protection of New Hampshire Forests wishes everyone a happy April 1. www.forestsociety.org.