VOL. 39 | NO. 47 | Friday, November 20, 2015
Emerald ash borer devastates Tennessee forests
By Ellen Margulies
The emerald ash borer is an unassuming little bug, an almost-pretty insect that could fit on the head of a penny with three or four of its brothers.
But these little green pests are weaving a wormy path of destruction through Tennessee’s lumber industry to the tune of $11 billion. That’s a lot of pennies, and a lot of emerald ash borers.
Since a new infestation was discovered in Mt. Juliet, Wilson County has now been added to the list of quarantined counties in Tennessee: No raw ash timber, firewood or live ash trees can be transported to any counties not included in the quarantine.
The bug was first discovered in Knox County in 2010, and by the next year, six Tennessee counties, Blount, Claiborne, Grainger, Knox, Loudon and Sevier were put under emerald ash borer quarantine.
There are an estimated 261 million ash trees in Tennessee alone, and the timber is used for everything from construction to firewood, in addition to being a popular residential shade tree. Since the emerald ash borer (EAB) was introduced to the U.S. from Asia, in the 1990s, the U.S. Department of Agriculture has been working to mitigate the economic and environmental damage. EAB beetles can kill an ash tree within three years.
Officials are hoping they can contain the exotic pest invasion before the popular ash tree goes the way of the American elm and chestnut trees, both of which were almost killed off in the U.S. through fungal and pest infestations in the early 20th century.
“The decline of the ash population is our generation’s chestnut wipe,” says Tim Phelps, information forester for the state. “None of these epidemics have caused any of these trees to go extinct, but it made them ecologically dysfunctional.
“Ash trees in our rural forests are a major component. They’re not the most dominant trees, but they produce food and shelter for wildlife.”
By working with federal officials and placing individual counties under quarantine, state Department of Agriculture forestry experts hope to avoid having to quarantine the entire state.
The Tennessee quarantine list is up to 47 counties, including Davidson, Williamson, Rutherford and Wilson, which is likely to be the final county quarantined this year, Phelps says. The 2014 list included only 39 counties.
“We wanted to try to control the spread of the insects a little tighter than the whole state,” Phelps explains.
“Once the quarantine is in place, it restricts the movement of ash to nursery stock, so we have folks who are working with nurseries. We are also working with lumber companies and sawmills that take logs from the woods and saw them into boards.”
A tree showing the damage done by the larvae of the emerald ash borer that feed on the inner bark of the trees, disrupting the tree’s ability to transport water and nutrients. The adult beetles, seen in photo above, nibble on ash foliage but cause little damage.
-- Www.Emeraldashborer.InfoOne of the biggest challenges, however, is getting the word out to everyone in the firewood business. When it comes to hardwood firewood, most consumers “don’t know the difference between ash vs. hickory vs. oak,” Phelps says.
“What is difficult is to track down everyone who sells firewood to get that information to them. There are just too many mom-and-pop operations and too many people who sell firewood on the weekends or just as a side business to get to everyone individually.”
Although the state is working on a directory, it’s not complete yet, Phelps says.
Bradley Hite, owner of NashvilleFirewood.com, 13306 Old Hickory Blvd., has been in the firewood business full time for five years. While he was aware of the EAB infestation, he didn’t realize the extent of the spread or of the damage.
A diseased tree in Knox County, where Tennessee’s infestation was believed to have started.
-- Submitted Photograph Courtesy Of The Tennessee Department Of Agriculture“It doesn’t affect us too much as long as you’re moving firewood from one (quarantined) county to another,” Hite says. “I haven’t really looked too much into it. I have told people who have come to get wood for, say, Florida that it’s better to get your wood in Florida.”
Hite says he has been getting more questions lately about where their wood is sourced, and two customers turned him down because they told him the campgrounds where they were headed required that their firewood come from a specific county.
“For the most part we’re only getting wood from Davidson and Williamson counties, and a little bit from south Davidson. This is the busy season. It starts to slow down and then it picks up again. The early birds have already got their wood.”
Luckily, there are plenty of other hardwoods to choose from, Hite said, including maple, elm, hackberry, cedar, pine, oak, locust, hickory and cherry. He hopes the state can help keep the infestation in check.
“I was unaware that it had gotten that bad but I knew we were having an issue with that beetle... if it gets to be a huge issue, it might cause a problem.”
Phelps says Tennessee is part of a pilot program, along with EAB-affected states of Michigan, Wisconsin and California, to create an online firewood vendor directory which could help consumers find locally sourced wood more easily.
“We’re working with local vendors of firewood so we can list them on this Google Maps platform directory. Consumers can punch in a zip code and get a list of firewood vendors. In the process, we can also encourage the consumer to ask the vendor where their firewood came from, and if they were aware of the problem,” he says.
Although experts estimate Tennessee might face damage in the billions – $9 billion rurally and $2 billion in urban areas – Phelps notes that those numbers could easily spiral if they can’t keep the EAB infestation in check.
The urban damage estimate is partially based on the cost of removing dead or nearly-dead trees, before they fall on the homes or buildings nearby.
“A lot of our cities are planted with ash,” he says. “Ironically, when the American elm trees were almost wiped out, guess what replaced them? Ash makes a beautiful yard tree, white ash especially. In the fall it turns a purplish-orange color, and it tolerates our soil really well.”
Unfortunately, once you spot the tiny beetles’ distinctive D-shaped holes in the bole of an ash tree, it’s often too late.
“It was discovered in Davidson County last year, and we’re basically on the clock to watch our ash population decline. In six or seven years we’re going to see a sharp increase in mortality,” Phelps says.