Your Feb. 28 editorial (“Forest products industry depends on biomass”) correctly identifies woody biomass as a centrally important component of the Maine forest products industry, and one which is vulnerable because of softening demand. In addition to its economic benefits, biomass is attractive because it is locally sourced and sustainable.

However, it is not correct to say that the burning of biomass is carbon-neutral. By cutting trees, we prevent them from removing carbon dioxide from the atmosphere and storing it in their stems and branches, a process known as carbon sequestration. Even dead wood contributes to carbon sequestration by adding organic matter to the soil, and studies have shown that forests hundreds of years old continue to accumulate carbon.

In February 2015, 78 prominent scientists sent a letter to the U.S. Environmental Protection Agency, explaining why biomass harvesting is a net contributor of carbon to the atmosphere. Policymakers worldwide are beginning to recognize that early claims about carbon neutrality of biomass were built upon faulty assumptions.

If Maine policymakers choose to subsidize the biomass industry in order to benefit Maine workers, claims for carbon neutrality should not be among their justifications.

Judy Stone

China