The Sierra Club report says old-growth trees should be considered non-renewable resources. (Garth Lenz/Canadian Press)

One year of logging old-growth forests in southwestern British Columbia blows away a year of carbon reductions accomplished by initiatives like the carbon tax.

That's the finding of a Sierra Club report released today, entitled Carbon at Risk: B.C.'s Unprotected Old-growth Rainforest.

According to the report, old growth forests store massive amounts of carbon, but cutting those trees causes them to belch the carbon into the atmosphere — while clearcuts or second-growth forests are unable to mop it up.

The report says old-growth trees should be considered non-renewable resources, protected from logging, because it takes up to 500 years for the forests to return to their previous status as massive carbon sinks.

But Coast Forest Products Association president Rick Jeffery disputes the findings, saying scientists also agree second growth forests store carbon and new growth actually grabs hold of more carbon than old-growth forests — which are essentially, tired, old and no longer expanding.

Jeffery says the Sierra Club is only interested in halting logging.