Out of the Firewood and into the Parlor

Redheaded ash borer. Photo: Mike Wilder, NCCES

These striking photos were submitted to the PDIC as an online image sample. Several of these insects had been found crawling around furniture in a Rocky Mount, North Carolina residence. Our soon-to-retire entomologist Dave Stephan identified them as the redheaded ash borer, Neoclytus acuminatus, one of the most commonly reported of our "firewood beetles." Although it is called the redheaded ash borer, it can infest many different species of hardwood trees. Dave also provided the following information about this interesting situation.

Redheaded ash borer. Photo: Mike Wilder, NCCES

There are several species of longhorned beetles which can emerge from firewood in homes. Most of the species encountered this way in North Carolina belong to the genera Euderces, Megacyllene, Neoclytus and Phymatodes. Typically, females of these species lay their eggs in the bark of recently cut, storm damaged, or dying trees. The hatching larvae tunnel into the wood and complete their development in one year, although some species may take 2-3 years. Longhorned beetles in general spend their grub-like larval phase burrowing in wood, eventually pupating there. There is a certain chilling requirement for the insect to break diapause (hibernation). In simple terms, if the wood stays out in the cold long enough, the insect's body is primed for spring. When the wood is brought into the house, the warmth tricks the beetles into thinking that the winter has passed, and the adults emerge. Dave suspects that the insect is as surprised as the homeowner to find that it has emerged into a strange habitat. He says that the chance is "less than zero" that they will cause damage to wood products in the home, since they must lay eggs on a "green" tree with intact bark. They do not sting, transmit disease, or carry off children, but could bite (just a pinch) if handled roughly. To avoid the problem in the first place, burn firewood within two to three weeks of bringing it inside.

Firewood can be a means of moving more serious pests, too. See Rob Trickel's Guest Blog from November 5, 2012 for more information.

Don’t Move Firewood!

Photo: Larry Grand

With a chill in the air and leaves turning brilliant colors here in Raleigh, our thoughts turn to cozy firesides, big bonfires, and warm campfires after a long day’s hike. With this in mind, we asked Rob Trickel of the North Carolina Forest Service for a timely reminder about the dangers of moving firewood. 

Invasive Pests and Firewood Movement

Non-native invasive forest pathogens and insect species have potential to cause great harm to North Carolina’s forests and landscapes.  The fungus that causes laurel wilt is killing redbays and swampbays in the Coastal Plain and we think it may also devastate sassafras across the state.  Other invasive diseases and insects that have the potential to cause great harm to walnuts (thousand cankers disease), ash (emerald ash borer), and a variety of hardwoods (gypsy moth) are found in counties in Tennessee and Virginia adjacent to our state (see current invasive monitoring map).  In addition, Asian longhorn beetle is devastating a wide variety of hardwood tree species in the Northeast and Midwest, and has the potential to do the same here.   All of these pests have the following in common:  they move naturally from place to place at a very slow rate, but can be spread rapidly if moved in firewood.

Emerald Ash Borer Galleries in firewood. Photo: Troy Kimoto, Canadian Food Inspection Agency

Moving firewood can introduce invasive pests to new ecosystems, where they can cause ecological, economical, and social problems in our forests.  In response to the rapid spread of emerald ash borer via firewood, some states have even enacted laws regulating the movement of firewood to slow the spread of invasive species.  North Carolina is approaching the problem with public awareness and education campaigns and has joined with other southeastern states to promote the use of local firewood or firewood that has been treated or certified to be pest-free.  

As part of the effort, the Changing Roles program of the USDA-Forest Service has developed two fact sheets about firewood movement as a means of spreading invasive species to new areas. These fact sheets help equip our partners who work with various audiences (consumers and producers of firewood) with information to combat the spread of invasive pests.

Fact Sheet 5.4 (Invasive Species and Firewood Movement) is firewood/invasive species 101 and covers:  What is firewood?  What types of invasive pests are transported in firewood? Why is the movement of firewood a pathway for the spread of invasive pests? What are the ecological, economical and social effects of invasive pests?  

Fact Sheet 5.5 (Preventing Firewood Movement) concentrates on how to engage a variety of audiences on firewood issues including:  How do we (foresters, extension staff, natural resource professionals) communicate with and engage different audiences on this important topic? How do we work with homeowners and outdoor enthusiasts (also parks and campground staff, arborists and green industry professionals, wood processors and producers) to combat the spread of invasive pests?  How is the movement of firewood regulated? And, where can I find more information about preventing firewood movement?

You can find more information about firewood movement and forest health, excellent images of the insects and diseases that can be spread by moving firewood, some very entertaining videos at www.dontmovefirewood.org   

Photo: Rob Trickel

 

Prepared by Rob Trickel, Forest Health Branch Head, North Carolina Forest Service