Mast Reforestation, a Seattle-based company dedicated to combating climate change through reforestation, has recently found itself embroiled in controversy over the integrity of its carbon credit projects.
The company, known for its innovative approach of selling voluntary carbon credits to fund tree planting efforts on land devastated by wildfires, acquired significant parts of the supply chain to bolster its operations.
This included purchasing Cal Forest Nurseries, the largest independent nursery in the Pacific Northwest, and Silvaseed, which boasts the largest privately held seed bank in the West.
In 2023, Mast successfully replanted approximately 2,500 acres in Montana and followed this achievement a year later with the launch of the Feather River Dome project near Chico, California.
Mast has marketed itself as a unique player in the carbon credit arena, claiming to be the only vertically-integrated reforestation carbon credit developer.
The company found support from Social Capital, a well-known Silicon Valley venture-capital firm.
However, the narrative took a troubling turn as allegations surfaced that Mast misled potential partners to secure its reforestation projects.
A crucial element in this controversy revolves around how Mast structures its carbon credits.
Like many firms in the industry, Mast sells carbon credits to businesses looking to voluntarily offset their emissions.
These credits are financial instruments often utilized to fund the preservation of ecosystems that sequester greenhouse gases.
Distinctively, Mast focuses on a type of carbon offset termed “ex ante” credits, which are based on predictions of future climate benefits, rather than measurements of current carbon capture.
This funding model relies on projections of future tree growth, meaning the costs are incurred upfront while the environmental benefits come in subsequent years.
Such a method introduces an element of speculation, raising concerns among experts like Danny Cullenward from the Kleinman Center at the University of Pennsylvania.
Cullenward pointed out, “Instead of observing what actually happens at the project, we project what we think is going to happen, and that’s even more speculative than the conventional carbon-crediting approach.”
The inherent risks in predicting forest growth are especially pronounced in regions vulnerable to drought or wildfires—characteristics of the areas where Mast conducts its reforestation projects.
Adding to the escalating crisis, Arnoud de Villegas, a former senior director of business development at Mast, filed a wrongful termination lawsuit in Siskiyou County, asserting that the company engaged in deceptive practices when dealing with potential partners.
De Villegas accused Mast’s CEO Grant Canary of making exaggerated claims about prospective deals and misrepresenting the value of its ex ante credits.
The lawsuit alleges that Canary frequently misled external clients and investors about Mast’s business operations.
In one instance, it is alleged that Canary suggested a prominent corporation would acquire a significant share of the carbon credits from the Sheep Creek Ranch in Montana, a statement he knew to be untrue, according to the lawsuit.
Concerns about these practices were shared by several employees, who spoke on the condition of anonymity due to fears of retaliation.
In January 2024, De Villegas and concerned staff sent a letter to the board requesting an assessment of Canary’s performance based on these unsettling tactics.
Despite this, the board announced that an independent investigation concluded without findings of wrongdoing.
Canary continued his push for projects, prompting De Villegas to delay actions due to his ethical misgivings, eventually leading to what he describes as an unbearable situation and resulting in taking medical leave.
His access to company email was suspended in May, and he argues that this was an effective termination of his employment.
Mast has chosen not to comment on the ongoing litigation.
As these events unfold, the voluntary carbon credit market is experiencing significant scrutiny.
Some experts, including Cullenward, observe that this period of heightened awareness follows years of academic and investigative reports identifying substantial issues within the industry.
A study published last year in Nature Communications revealed that only 16% of carbon credits issued to various projects actually contributed to emission reductions.
The report concluded that fundamental reforms are necessary for carbon crediting mechanisms to truly aid in combatting climate change.
This has contributed to a general decline in the market prices for carbon credits as buyers exercise increased caution.
Carbon Streaming Corp, which invested $15 million into Mast, reported a total markdown of the Sheep Creek reforestation project to zero after widespread seedling mortality.
A corresponding decline was also noted for Mast’s Feather River Dome project.
In its latest fiscal report, Carbon Streaming stated that the carbon credit market is shifting towards lower-risk credit options, as the demand for ex ante credits—characteristically more speculative—has diminished.
Despite the downturn in interest for these types of carbon credits, Mast reported that it had still planted around 47,000 native seedlings across 165 acres of its Feather River Dome project in Butte County, California.
Additionally, the owner of the Sheep Creek Ranch confirmed that his property had been replanted by Mast.
In a statement to Jefferson Public Radio, Mast acknowledged that the voluntary carbon market has undergone a “period of reckoning” but expressed optimism about its future.
The company highlighted that the marketplace is evolving and that higher buyer expectations could be advantageous for projects rooted in high-integrity carbon removal and ecological restoration.
In its latest endeavor, Mast launched a biomass burial project to address the demand for more immediately realizable carbon credits, wherein dead trees are buried to prevent the release of carbon dioxide during decomposition.
In February, Mast announced it secured $25 million in Series B funding for this novel biomass burial venture.
Notably, this marks not the first time Mast has pivoted its strategy; previously, the company, originally named DroneSeed, aimed to use drones for aerial re-seeding—an approach met with mixed results.
Mast maintains that the validity of its projects remains sound, asserting that the issue lies within market structures that have not aligned with reforestation timelines.
A former employee voiced concerns, expressing hope that challenges posed by a minority of companies in the voluntary carbon credit sector don’t tarnish the model’s potential for genuine climate change mitigation.
Justin Higginbottom is a reporter with Jefferson Public Radio, and this article is part of the Northwest News Network’s collaboration between public media organizations across Oregon and Washington.
image source from：https://www.opb.org/article/2025/06/08/mast-reforestation-whistleblower-lawsuit/
