The Wisconsin Department of Natural Resources (DNR) is considering the need to alter the classification of emerald ash borers as their infestation in Wisconsin's forests has increased.

The emerald ash borer has become widespread in North America over the last several years, with the destructive insect spreading throughout the US and Canada. It burrows deep under the bark of ash trees to lay its eggs, and when the larvae hatch they begin to feed on the tree from the inside until the tree dies.

Since the ash borer is an invasive species, there are no predators in place to control the insect's growing numbers, resulting in widespread damage to ash trees throughout the continent.

The Wisconsin DNR has an invasive species catalog that was created five years ago. It features emerald ash borer and several other insect, plant and animal species as unwelcomed guests.

The list features two distinctions that includes prohibited species and restricted ones. Under DNR guidelines, prohibited species are banned from being sold, possessed or transported. Moreover residents are legally obligated to destroy any specimens of a prohibited species discovered on their property.

This holds opposite views from the way restricted species are handle, while they're also barred from transport or sale, it's not required to destroy any specimens. According to DNS, the ash borer infestation is simply too great to expect property owners to destroy the insect whenever it's found.

Out of the 72 counties that make up Wisconsin, the DNR says that the tree-destroying insect has been found in 28 of them so far.

Most US states are trying to limit ash borer populations through geographical isolation. People have been warned not to transport live ash trees or firewood originating from the tree out of their neighbourhood to help slow the spread of the insect.