Ash Bore Beetle Destroys 67,000 Trees Costing Taxpayer $36 Million

After 15 years of relentless work to combat the spread of the Emerald Ash Borer beetles, the cities of Minneapolis and St. Paul have completed the removal of the last ash trees from public spaces, marking a major milestone in Minnesota’s fight against the invasive beetle. Almost all remaining ash trees have been treated to protect them from infestation.

The Emerald Ash Borer (EAB), a destructive insect first discovered in Minnesota in 2009, has posed a severe threat to the state’s ash tree population. Minnesota is home to one of the nation’s largest concentrations of ash trees, estimated at 1 billion, most of which grow in forested areas.

Tens of thousands, however, were located in the Twin Cities, making the removal effort in Minneapolis and St. Paul a critical component of the state’s overall strategy to contain the infestation.

“The first infestation of EAB in Minnesota was discovered in Saint Paul in 2009, though it is believed it arrived as early as 2004,” Clare Cloyd, Public Service Manager for the City of St. Paul, told Newsweek.

“While EAB spread starts slowly, it produces exponentially and advances quickly en route to killing all ash trees within a community, usually within 10-15 years of arrival.

“The larvae are grub- or worm-like and live underneath the bark of ash trees. Trees are killed overtime by the tunneling of the larvae under the bark.”

Over the last decade and a half, St. Paul has spent about $36 million managing the emerald ash borer and treating public trees, including 112 that remain in parks. Additionally, private residents have funded treatment for over 800 ash trees on public property.

“The primary strategy for managing this environmental crisis centered on structured removal, or the complete removal of ash trees on full city blocks,” Cloyd said.

“The plan then called for stumping and replanting each tree overtime with the goal of a 1:1 replacement of a more diverse pallet of new trees. In June of this year, our Foresters completed the last block of structured ash removal, roughly 15 years after its arrival to the city.”

But the battle isn’t over. Some individual ash trees remain on boulevards, and private ash trees across St. Paul require attention. In addition, 350 boulevard trees that adjacent property owners elected to treat and most are still being treated at the expense of the property owner, Cloyd confirmed.

Despite the overall success of the scheme, the whole process has taken a significant toll on the communities affected.

“Our foresters often talk about how they did not go into the field to focus on removing trees, but for the passion they have for caring for and improving our urban forest,” Cloyd said. “There is a collective understanding of the value of trees for the aesthetic and environmental benefits they provide, especially in an urban area.

“While this has been a long and at times arduous process, a diverse set of healthy new trees in the place where the ash once stood sets us up to continue realizing the benefits trees provide to our city for generations to come, especially as we face the mounting impacts of climate change.”

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