Golden Valley surrendering to emerald ash borer

These bright green beetles may be smaller than pennies, but they have killed millions of ash trees.

Golden Valley has been condemning trees infected with emerald ash borer, but now the city appears to be resigning in the fight against the bug.

Under the existing ordinance, property owners are required to swiftly remove infested ash trees. If ordinance 779 is approved, property owners will no longer need to remove infested ash trees from their property.

Emerald ash borers, first witnessed in Minnesota in 2009, got to Golden Valley in 2018. Now they have overtaken the entire metro area, southeastern Minnesota and beyond.

Adults lay eggs on trunks and branches in the summer. Larvae hatch and tunnel under the bark. Ash trees are then devoured by the bugs as they grow up. Bugs will emerge later as adults, mate and lay eggs. Unless they’re treated, the ash trees are fed upon until they die.

The Minnesota Department of Agriculture developed some guidelines for dealing with the emerald ash borer. MDA has recommendations for planning, inventory, monitoring removing trees, sanitation, wood management, replanting and biological control. Tactics vary depending on if the area is not infested, generally infested, or heavily infested. Golden Valley is in this heavily infested stage.

Mark Abrahamson, director of MDA’s Plant Protection Division said most of the efforts against invasive species are slowing the spread of the Emerald ash borer from southeastern Minnesota as well as the spongy moth from northeastern Minnesota.

“Preventing spread is impossible with insects,” Abrahamson said. “(Because) they can move themselves. Spongy moth is able to move on its own. Emerald ash borer can fly on its own, as another example, but it’s a slow spread. They can only go so far under their own power. So slowing the spread is really about preventing the human-assisted movement.”

It is no longer possible to prevent the spread of the emerald ash borer within the infected area, but people can take steps to prevent things from spreading outside the area.

Abrahamson said a concern in the Twin Cities is the safe disposal of all the infected trees. People might transport untreated firewood from an infected area, not realizing this is illegal. There are a number of state laws and local ordinances regarding firewood. Go to dnr.state.mn.us/firewood to learn more about current regulations regarding firewood transport.

The MDA is attempting to slow the spread in order to learn more ways to manage the infestation.

“There is an element of buying time,” Abrahamson said. “Not only because all the areas that don’t have that pest yet are benefiting from all the years they can get without it, but then also there’s always an opportunity for things to be discovered that might help manage it.”

Emerald ash borers originated in East Asia, where trees there are able to better resist it. There has been some research into species of ash trees that might better resist the beetle.

On Feb. 6, the Golden Valley City Council took a look at the new ordinance and gave a first reading.

“Staff is proposing to discontinue the condemning of ash trees on private property,” Public Works Director Tim Kieffer explained. “Staff will continue to help property owners to manage their ash trees as they see fit, but requiring them to promptly remove it sometimes can be a financial burden.”

The city will continue to condemn trees infected with oak wilt fungus and Dutch elm disease fungus. Once condemned, people have 20 days to remove the tree.

Abrahamson noted that a key difference with oak wilt or Dutch elm is that the fungi can be noticed right away. Emerald ash borers may eat a tree for several years before infestation is apparent.

When there is a hazardous tree that is not infected, it is usually up to the property owner and their neighbors to determine the course of action. If people in the city have a question about their trees, they can reach out to Tim Teynor, city forester at 763-593-3976.

City Attorney Maria Cisneros said the city monitors and removes trees in public right-of-way, but hazardous trees on private property are a little different.

“We don’t have a practice of removing trees from private property,” Cisneros said, “Although, this ordinance does allow us to do that in certain circumstances if we allow give proper notice and then assess the cost of that back to property owners.”

Cisneros added that would only be for “an extraordinary circumstance.”

The council voted 5-0 to approve the first reading. A second public hearing and reading for proposed ordinance 779 is slated for 6:30 p.m. Tuesday, Feb 20, 7800 Golden Valley Road, Golden Valley. The meeting will be available to stream live at goldenvalleymn.gov.