The emerald ash borer has the potential to drastically alter Minnesota's ecosystem.

First discovered in St. Paul on May 14, the pest is believed to have lived and spread in the state for three to five years before it was detected, said Mike Schommer, Minnesota Department of Agriculture communications director.

The borer is deadly to all three types of ash native to Minnesota: Green ash, white ash and black ash. Green ash are found throughout the state, with black ash predominant in the north and white ash in southeastern Minnesota, primarily along the Mississippi River and its tributaries.

Ash is the third most abundant species in the state's forests, said Susan Burks, invasive species program coordinator for the Minnesota Department of Natural Resources forestry division.

Minnesota and Maine are said to have more ash trees than all other states, said Mike Reichenbach, University of Minnesota forestry Extension educator.

While ash trees are logged, with more than 71,000 cords harvested in 2007 valued at $15 million, Reichenbach says their ecological value is much greater. There are 149 vertebrae species who use black ash in some way or form, he said.

"We don't know what the loss of ash will do to our ecosystem," Reichenbach said.

In the late 1970s and early 1980s, a lot of talk centered on the threat posed by acid rain. It could cause acidification of Minnesota's lakes, he said. That was the same time the elm disappeared from the landscape. Some suspect this contributed to the acidification of lakes and changing lake ecosystems.

The ash tree isn't the first to face extinction from a foreign invader. Both the elm and the American chestnut were virtually wiped out by invasive diseases. Blight killed chestnut trees along the Eastern seaboard prior to 1930. The elm was decimated from 1930 when the first case was discovered in Ohio to the early 1980s.

Like the emerald ash borer, the chestnut blight arrived via commerce. It's believed chestnut blight hitchhiked to the United States on a shipment of logs, Reichenbach said. It's believed that emerald ash borer arrived on wood pallets from Asia, he said.

Wood pallets are a mainstay of commerce, yet they have the potential to harbor insects and diseases, Reichenbach said. A treaty that's been in place for at least four years requires heat treatment for pallets to kill insects and diseases.

However, heat treatment of pallets is expensive and wood farmers are concerned about absorbing the additional cost. They are also concerned that manufacturers will shift away from wood to another material.

In the meantime, Minnesota officials are asking for the public's help to slow the spread of emerald ash borer to give researchers time to perhaps discover biological controls.

Asia has ash trees. Reichenbach said different trees generate chemicals that protect them from the borer. Perhaps, researchers can find native ash trees that have similar capabilities.

He's optimistic that the public will have an impact on slowing the pest's spread because they want to do the right thing.

If the tree is lost, Native Americans will lose a part of their culture. In Minnesota and throughout the northeastern United States, Native Americans use black ash trees for basket making. It's become increasingly difficult for them to find black ash trees to use for their craft and now the emerald ash borer threatens to destroy all ash trees.

"From a social standpoint, we stand to lose alot," Reichenbach said.