Wisconsites weren't the only ones upset by the area's recent polar vortex, bringing temperatures of minus-20.

Emerald ash borers can be harmed by the low temperatures.

The invasive species, named for the ash trees it destroys, was confirmed in Hudson in July last year, off Crest View Drive and in the town of Hudson along Fraser Lane. The larvae spend the winter under the bark of the ash trees, according to the Minnesota Department of Agriculture. An abundance of larvae in a tree kills it.

A study from the Minnesota and U.S. Departments of agriculture showed nearly 80 percent of ash borer larvae could be killed when temperatures reach 20-degrees below zero. The rate increases to 98 percent at 30-degrees below zero.

"It will kill some of the larvae, but not all of them," Hudson Public Works Director Mike Mroz said.

That means that, unfortunately, emerald ash borer is here to stay, he said.

"It will slow down the spread, but it won't be a complete total kill where all of a sudden Hudson doesn't have emerald ash borer," Mroz said.

While it won't eliminate the invasive pest, the cold weather will give the city more time before it sees the effect of the species. It will take a couple years for the borer to get back to normal population.

"What it does do though is it buys us maybe another year or two," Mroz said.

During that time, the city will continue with the plan it created back in 2012 to address emerald ash borer. The possible impact of the cold won't lead to any adjustments of that plan.

"We'll keep plugging away at it," Mroz said.

The city has already removed ash trees that have been identified as high-risk. Now the city is focusing on the smaller ash trees, those a foot in diameter or less.

The city is also continuing to chemically treat 10 percent of the ash tree population in the city.

Hudson was recently awarded an urban forestry grant from the state that will be used in part to fund the removal and treatment of ash trees.

Resources for residents to deal with private ash trees are available on the city of Hudson website.