Q. With global warming in mind, given that trees absorb much of Earth’s excess carbon, and given that burning wood produces unwanted carbon, which is the more viable for heating a home: oil or wood?

Laurie Stearns of Brunswick, and Bill Stearns of Milford

A. If carbon dioxide in the atmosphere is the focus of concern, then wood burning is much to be preferred to oil burning. The carbon in wood burns to carbon dioxide; but if the wood were to rot (or decay), the metabolism of the bacteria also would produce the same quality of carbon dioxide.

Wood burning is a wash in carbon dioxide generation. As much carbon dioxide is absorbed in the growth of the wood as is released in the burning of the wood. Was it Robert Frost who used the line: “the slow smoldering combustion of decay”?

Wood is renewable, oil is not. Wood is here, oil is “over there.”

Answer provided by Richard C. Hill of Old Town, retired emeritus professor of engineering at the University of Maine.