Is N.D. next?
Tree-killing beetle found in Minn.By WHITNEY PANDIL-EATON, Staff Writer wpandileaton@minotdailynews.com
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The Emerald Ash Borer
A native of Asia, the Emerald Ash Borer was first discovered in southeast Michigan in the summer of 2002 and has since spread to 10 states from Pennsylvania in the east to Iowa and now Minnesota in the Midwest. It has also been found in two Canadian provinces. In less than a decade the beetle is estimated to have killed 30 million ash trees in North America.
The beetle is believed to have arrived in the United States in the 1990s hidden on solid wood packing materials used in cargo ships and airplanes. Experts believe the infestation is spreading by people transporting infected firewood, logs or saplings. The United States Department of Agriculture has imposed restrictions and in some cases bans on the movement of wood in infected areas in an attempt to curb the spread, but the recent announcement of its appearance in Minnesota indicates the continued spread. Other suppressive measures such as the use of pesticides have so far been proven costly and labor-intensive.
The devastation comes not from the outside but from within.
While adult EAB beetles do feed on ash foliage, the real destruction begins after the female lays approximately 80 eggs on the bark of the tree. Emerging from the egg is a larvae which burrows into the bark to feed on the living wood, leaving a serpent-like trail which cuts off conduits that carry water and nutrients to every part of the tree. After developing into an adult beetle, it bores out of the bark, leaving a telltale D-shaped hole and goes out in search of a mate. Although trees can survive for a few years after the initial infestation, the beetle has a 100-percent tree mortality rate. The prime season for the beetle is May through September.
Minnesota became the 10th state in the United States to confirm the presence of a devastating beetle that has been linked to the destruction of millions of ash trees across North America.
Now many experts across the state are now asking themselves, "Are we next?"
"It was shocking to see it show up in St. Paul, but I know it's only a matter of time before it shows up here too," said Michael Kangas, a forest health specialist for the North Dakota Forest Service. "It's still probably a few years away, but it only takes one slip-up to start."
A native of Asia, the Emerald Ash Borer was accidentally introduced in the United States in the 1990s on wood packing materials used on cargo ships and airplanes. Since its introduction, the beetle has been linked to the destruction of nearly 30 million ash trees spanning 10 states.
According to the state Forest Service, there are 46.9 million ash trees in North Dakota's forests and woodlands, estimated to be worth $3.55 billion and another two to three million ash trees in communities and rural plantings such as living snow fences and windbreaks. Ash is the most common tree planted in North Dakota Communities and green ash represents the largest percentage of the state's 55,000 miles of shelterbelts.
For the past five years, the Forest Service and the North Dakota Department of Agriculture have been conducting surveys across the state, concentrating their efforts to areas at greatest risk of introduction including campgrounds and high traffic areas of wood materials. Mailbox-size purple sticky traps bated with Manuka oil are the primary tool, but Kangas acknowledged that the lack of scientific understanding of the insect and ineffective trapping methods have hindered progress.
"By the time the beetle is discovered, it has already been in the area for three or four years," Kangas said. "Preventive measures such as quarantines have not been useful to eradicate the pest and has had limited success in slowing the spread of it, so our focus has been on education."
That education includes the use and transportation of firewood, the diversification of foliage planting and the identification of signs of an infestation.
"We didn't learn our lesson from the Dutch Elm disease. We went with the second best species and now are facing a similar situation," Kangas said. "The greatest impact will be in the communities because nearly 60 percent of tree canopy is ash and they are all at risk."
The Forest Service has estimated that it would cost $600 for removal and replanting of each mature ash tree, a direct cost to a city. That translates into a cost of approximately $8 million in Fargo and $5.2 million in Bismarck, with little hope of federal or state assistance Kangas added.
"Those (figures) don't take into account the loss of cost-savings either. Home heating costs in the winter will go up without the windbreaks and cooling costs in the summer will rise too without shade. Wildlife that depends on them for cover or food will suffer as well as the quality of life. What is it going to look like after they're all gone?" said Kangas.
With approximately 4,000 ash trees spread across Minot, the potential cost of an infestation is estimated at $2.4 million.
"Throwing together the economic loss of cost-savings for homes, the visual impact and labor, the cost to the city will be phenomenal, but my biggest concern now is the fact that we are a small, underfunded department. An infestation could dramatically take away from our daily chores," said Brian Johnson, city forester. "It didn't surprise me that it hit Minnesota. Having done research I knew they could survive the cold climate and knew it was a matter of time became they came but I figured we would have five years back in 2007. (The discovery in Minnesota) has definitely opened our eyes to the fact that it is moving a lot faster than previously thought."
A contingency plan to tackle the budding issue is scheduled in the near future, Johnson said, but in the meantime his crew is being proactive by doing visual inspections on each ash tree removed in the city and will begin next week to set up 14 purple sticky traps throughout the area, from Velva and along the river in Sawyer to each corner of the city.
"People with dead or declining ash trees don't need to panic because many times native ash borers go after sick or dying trees, so send a wood sample to a city forester," said Kangas. He added that when it does arrive, "people will play an important role in the early detection of this beetle."
