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Chemistry, Materials & Packaging
As Forests React to Climate Change, Can Genetically Modified Trees Stand in the Gap?

In the lab, Living Carbon’s GM poplars accumulated biomass up to 53% faster, trapping as much as 27% more carbon than non-engineered poplars. But skeptics aren’t convinced they’re seeing the forest for the trees.

Climate change requires human and non-human communities to rise to their fullest potential in order to adapt, survive and thrive. The question of if, and how, some organisms could be helped along the way in reaching this potential and beyond is being explored by genetically engineering organisms to be more suited for a warming planet.

Biotech startup Living Carbon has developed a genetically engineered hybrid poplar tree with enhanced photosynthetic abilities. In lab conditions, Living Carbon’s poplars accumulated biomass up to 53 percent faster than non-engineered poplar trees, trapping as much as 27 percent more carbon.

Living Carbon has planted over 8,000 of its genetically engineered hybrid poplars in Georgia to see just how well these modified trees hold up in real-world use cases. The GM trees are all female to inhibit reproduction and allow the trees to integrate with local ecosystems.

It’s no shocker that the public distrusts genetically modified organisms; and Living Carbon CTO and co-founder Patrick Mellor thinks this is justified. Partially. GMOs are often used to breed herbicide-resistant plants; and the practice has become concomitant with industrial monoculture and the pesticide industry. And because many genetically modified seeds are patented, many are uncomfortable with the concept of life as intellectual property — the whole setup lending to viewing GMOs through Monsanto-tinted glasses.

But for Living Carbon, the potential for genetic engineering (GE) as an adaptive and mitigative tool for climate change is a totally different ball game than breeding GE commodity crops.

“[Genetic engineering] can have integrative and restorative effects when practiced with intentions other than maximizing crop yield within a monoculture, or extending product life,” Mellor told Sustainable Brands®.

The forest for the trees: Biodiversity vs carbon

Accelerated carbon absorption, disease resistance, boosted yield — GMOs are often designed to fit a particular purpose and not necessarily the holistic needs of the host ecosystem. Crops didn’t need to be, because of their nature as monocrops. Trees, however, are in the wild; and any manipulation of their genome must balance the overall needs of the local ecological community.

In the case of trees, how do we balance ecological and social benefits with the need to draw carbon out of the atmosphere?

“I don’t think the two are in conflict with each other, as long as you’re being honest with what will actually store carbon,” said Anne Petermann, co-founder and coordinator of the STOP GE Trees Campaign. “What’s best for communities and the environment is what’s best for the climate.”

Focusing on amassing individual trees for sequestration misses the forest for the trees by overlooking the way species interact with each other as well as boosting ecological services, diversity and net carbon sequestration throughout the ecosystem. Viewing trees simply as a way to balance the carbon budget, Petermann says, is a grossly inaccurate view of how natural systems sequester carbon.

Climate change will make it difficult for trees to hold a grip to their native ranges, let alone novel GE species, Petermann explains. Tree migration is imminent, exemplified by devastating drought and wildfires and “zombie forests” surviving in places they can no longer regenerate. Putting untested genomes in an unpredictable climate is risky, she insists, and doesn’t take into account the ways a changing climate will affect disease, drought, pests, land use and more.

While Mellor admits it is true that genomes are complex in the sense that they are unwieldy, they’re not so finely tuned that a little genetic meddling will produce monsters. Still, he doesn’t rule out the accumulation of “small effects” in modified genomes resulting from prolonged interaction with the local ecology.

“This is why we are taking an incremental approach to the deployment of our trees — progressively introducing them at larger scales, so we can observe these effects in real time and continue guided by our previous observations,” Mellor said.

The Arbor Day Foundation acknowledges the potential of genetically enhanced tree species; so it’s keeping tabs on developments that could help forests become more biodiverse and resilient.

“We need an all-hands-on-deck approach; and we need to sequester a lot of carbon, like, today — but not at the expense of other things,” Pete Smith, urban forestry manager at the Arbor Day Foundation, told SB. “If one [solution] comes at the expense of another, it becomes a race to the bottom and not an exercise on how we solve the greatest issues facing our day.”

Projects such as Living Carbon attract innovation, Smith said; and chances are, they’ll help prompt a new bloom of cleantech innovation to complement the systems nature has already provided.

Just like any investment portfolio, a failed forest project can be avoided through diversity, he added. While GMOs are on the proving grounds, Arbor Day is focusing on other solutions that are proven to be effective and scalable — such as the Foundation’s work on an interactive map predicting future plant-hardiness zones in the wake of climate change.

Whether a GE or indigenous tree, climate-resilient ecosystems are about more than just putting roots into the ground. Both Petermann and Smith are critical of any carbon-sequestration project that comes at the expense of social justice and biodiversity. Petermann sees GE trees as yet another enabler of the status quo — a way to draw down carbon faster in order to sell carbon credits faster in order to “offset” ballooning emissions.

If Living Carbon’s lab results are true, that makes its GE hybrid poplar an attractive asset for forestry-based carbon-offset solutions. While Petermann is concerned that the hybrid poplars will enable monoculture plantings, Mellor says Living Carbon’s poplars are being planted in mixed timber stands situated on degraded land. Contracts stipulate that the trees planted now cannot be cut down for at least 10 years; and when they are, they must be turned into durable wood products rather than pulp — meaning less potential for landfilled, single-use forestry products emitting climate-changing methane.

Living Carbon sees itself as providing biological assets enabling regenerative forestry — in which trees draw down carbon; become carbon-storing, durable wood products; and all forestry waste (or “slash”) is converted into valuable biochar or bio oil.

“We represent a pioneering approach to the application of integrative, synthetic biology in multiple species to enable carbon drawdown,” Mellor said. “Calling this ‘selling offsets and enabling business as usual’ is reductive misrepresentation. We are not planting monocultures; we are building biodiverse forests.”

“Progress is so important right now — and there’s no perfect option,” Smith admits. “It’s not an excuse to do bad work; but something that gets me through the day is this momentum against the challenge of climate change.”

The hybrid poplar is the first of Living Carbon’s portfolio of photosynthesis-enhanced GMO trees. The company says subsequent tree types will focus on carbon absorption and slowed decomposition.

Living Carbon has submitted a manuscript for peer review but is unable to provide further details. Lab results relating to its current GE hybrid poplar can be found in this whitepaper.