It's an exotic beetle native to Asia, discovered in the United States in 2002.
Since that discovery, the Emerald Ash Borer has now spread to 29 states, including Minnesota.
And it's been killing trees ever since.
Minnesota has over 900 million ash trees, the most of any state, so the potential for damage from the beetle is tremendous.
First discovered in Rochester in August of 2014, the number of cases of trees infested with Emerald Ash Borers only escalates.
"We've confirmed about 60 to 70 trees this year, we had confirmed about 12 all of last year,” said City Forester Jeff Haberman.
What's more, trees have been found in almost all parts of town.
"We found it in three out of the four quadrants of the town. The only one we haven't found it in, so far, is the Northeast,” Haberman added.
What happens is this: The adults lay eggs between crevices in the bark of the ash trees.
Once the eggs hatch, the larvae tunnel underneath the bark, feeding on it.
This feeding on the bark, in turn, prevents the trees from transporting water and nutrients, ultimately leading to the death of the tree.
The trees will typically die within six to eight years.
The Parks and Rec Department has created a possible solution to the EAB problem.
"The city has a EAB management plan that calls for treating our best half of the public trees that we have in our inventory," explained Haberman.
That treatment consists of injecting the trees with insecticides.
“We began our injection program last year. And we treated about 425 trees. And we'll continue to increase the number that we treat every year until we get to that 2300 which is ultimately what we're trying to protect,” said Haberman.
He added, “My biggest concern is to protect those trees that we have made a commitment to save and not let them die.”
But what about those ash trees at private homes?
Haberman spent Tuesday night educating homeowners of their options.
“They only have two options: Either you spend money removing them or you can spend money saving them," educated Haberman.
Haberman added in that treating two trees for 20 years costs the same as removing just one tree.
So he suggests treatment over removal.
"The tree will not die from EAB as long as it's being treated," said Haberman.
Who knew such a little insect, can cause such widespread harm?
Haberman also wanted to remind everyone that if you have firewood, do not, by any means transport it.
That is the most common way to spread the Emerald Ash Borer.