Dear Don't Move Firewood,
I am on the Board of Directors for my community in (town near Denver), Colorado, and I want to spread the word to my community about moving firewood. I am unclear on one thing: Is firewood bought from the grocery store, or a big box store, okay if it is sourced from far away? Thank you!
Dear Concerned Citizen,
You are right to be a little perplexed about how and if large stores purchase firewood wisely. While large stores are going to be very careful to source their firewood supplies legally, the legal rules in place actually aren't fully protective against certain forest pest situations. For instance, many forest pest infestations take years to be discovered- and all that time, firewood could be shipped hundreds of miles away to be sold at your town's chain gas stations, large grocery stores, and "big box" retailers. Likewise, native forest pests could be present and not subject to quarantines- yet moving these pests hundreds or even thousands of miles in firewood can pose a very real risk to forests and trees.
I inquired with my colleague Mitch Yergert, Director of the Colorado Division of Plant Industry, to see what his official statement might be for Colorado firewood. He said, "Because there are no national firewood regulations, we have no way of knowing what pests firewood imported from outside of Colorado may be harboring. Therefore it is much better to purchase firewood produced locally so that the chance of moving plant pests is greatly reduced."
This bring us to- what is local? when is firewood actually local? That's a really tricky question- in Wisconsin, the regulation is 10 miles from wood source to burn location. In many states, the guideline or regulation is 50 miles. For Colorado, the guidelines are not mileage specific, but instead authorities suggest "as close as possible" whenever feasible, and always from within the state of Colorado itself. Additionally, because of the presence of both non-native and native forest pests (emerald ash borer, thousand cankers disease, mountain pine beetle) in Colorado trees, it is extremely important for Coloradoans never to take firewood with them out of state, or even to different communities within the state.
The one notable exception to these out-of-state concerns is wood that is certified as heat treated, with USDA-APHIS heat treatment seal on it. This wood is heated in a kiln to a specific high temperature, for a set duration of time to "cook", which kills all potential pests in the wood. Packaged and labeled heat treated wood like this is safe to use even if it is from many states away. However, wood with a certified heat treatment seal is not widely available in Colorado, so it isn't a great solution to the general regional question. (Learn more about heat treated firewood, and how it is not the same as just kiln dried firewood, here)
Best of luck with your educational efforts!