JoAnne Skelly: Retail firewood transports live pests

Brr, it’s cold outside and many of us are burning firewood in our homes to keep warm. “A new study published in the Journal of Economic Entomology reports that live insects were found in 47 percent of firewood bundles purchased from big box stores, gas stations and grocery stores in Colorado, New Mexico, Utah and Wyoming.” Firewood sales are one of the main ways insect and disease pests are transported from infested areas to uninfested areas. Wood is often transported hundreds to thousands of miles, across state and even national borders.The researchers found that 52 percent of firewood in their study came from out-of-state sources. Approximately 47 percent of the firewood purchased in the study was infested with live insects. There is no single wood type that can predict live insects in firewood; although pine contained insects most often in this study. Pieces of bark were present on 85 percent of bundles. The presence of bark is a risk factor for future insect infestations. Ninety-three percent of insects that did emerge came out of firewood with at least one piece of bark on it. Insects were 80 to 93 percent likely to emerge from wood that showed signs of previous infestation. Insects emerged on average within 80 to 440 days of purchase on 52 percent of bundles. Insects emerged from some proportion of firewood purchased at box stores, gas stations and grocery stores (the study did not include independent dealers) in 13 of 21 states.The study proved that retail firewood can spread a wide range of insects and plant diseases. There are no national regulations on commercial firewood that require wood to be treated before transport or sale. Many state and federal agencies are trying to limit the distance firewood can be moved from its origin. However, heat-treating firewood before it is shipped would be a more efficient way to kill unwanted travelers before they become pests damaging our forests and ornamental trees. This would also be more beneficial to the firewood industry than banning firewood movement across state borders. The researchers suggested that working with retail chains to educate them and their customers would be more effective than trying to educate through independent dealers because retail chain impact is so great (*Jacobi, Hardin, Goodrich and Cleaver, October 2012).University of Nevada has a new publication out called “Insects in Firewood.” Contact me for a copy, 887-2252 or skellyj@unce.unr.edu.• JoAnne Skelly is the Carson City/Storey County Extension educator for University of Nevada Cooperative Extension and may be reached at skellyj@unce.unr.edu or 887-2252.