Expert questions climate value of Hesburger’s planted forest

A forestry engineer says a forest planted for Hesburger on a former peat field in Reisjärvi is unlikely to capture emissions as intended, Yle reports. He also questions a separate 4H tree-planting project in Kärsämäki.

Heikki Ala-aho, a forestry engineer and environmental planner, inspected the roughly eight-hectare site in North Ostrobothnia. He initially thought the planting looked successful, but changed his assessment after walking further through the field. Many saplings, he said, had been overtaken by other vegetation.

Carboreal, the company that planted the trees, says the work in Reisjärvi has gone better than usual. It plans to replace dead saplings and says vegetation has already been cleared and will continue to be managed. The company and 4H have described Ala-aho’s assessment as too pessimistic, according to Yle’s summary.

Raisa Mäkipää, a research professor at the Natural Resources Institute Finland and a member of the Finnish Climate Change Panel, says planting trees on peatland is not, in itself, a climate action. Drained peat continues to decompose and release emissions, which can exceed the amount of carbon absorbed by trees. As many as half of efforts to establish forests on former peat fields fail, she says.

Mäkipää says emissions from peatland could be sharply reduced or stopped only by raising the water table, which would require blocking the drainage ditches or allowing them to become blocked. That would favour trees such as willows, black alders and downy birches rather than commercially valuable pines and spruces.

She says planting is still a better option for the climate than leaving former peat fields or peat extraction sites as they are. Continued cultivation is the worst option because repeated soil disturbance produces the highest peat emissions. Finnish research on emissions from rewetting is limited, she says.

Hesburger says it does not use the planting project to offset its emissions or count it as an emissions reduction. The company says it was not aware of failures at the Reisjärvi site and was told dead saplings would be replaced if necessary. It says it will require corrective action if needed.

Carboreal chief executive Salomo Vilen says simply not cultivating the former field is already a climate action.