Emerald ash borer has now moved a little farther into Minnesota. The state’s Department of Agriculture announced on Thursday that Chisago County has become the ninth Minnesota County to be infested by the pest.

The state’s Departmnet of Agriculture also stated that they have also spotted some tunneling in a tree where the invasive pests were spotted.

The specimens collected from the survey trap have been sent to the US Agriculture Department for confirmation. The Star Tribune reported that the Chisago County likely will be placed under emergency quarantine in the coming week.

Officials said the county will join other counties where the invasive pest has already invaded. Anoka, Dakota, Fillmore, Hennepin, Houston, Olmsted, Ramsey and Winona are in a state and federal quarantine.

As per experts, emerald ash borer larvae kill trees by tunneling into the wood and feeding on the tree's nutrients. The insect was discovered for the first time in Minnesota in 2009.

The emerald ash borer has now been confirmed in two more Wisconsin Counties. It has also been confirmed in the town of Dayton in Richland County and the town of Montello in Marquette County.

Totally 38 counties in the state are under a quarantine, which means firewood can't be taken from a quarantined county to a non-quarantine county.

Mark Abrahamson, an entomologist with the state Department of Agriculture, said, “We’re reaching a period where it may start to build and spread more quickly, and that’s something that has been seen repeatedly in places where emerald ash borer has been found”.