An invasive species of insect that kills ash trees is cropping up in new areas of southwestern Ontario, posing a threat to 
forests, woodlots and even residential landscapes.

The emerald ash borer, a green beetle native to Asia, has been blamed for the loss of millions of trees across North America.

The insects are slowly spreading and it's could be too late to stop the population increase, according to Saugeen Conservation Area forestry manager Jim Penner.

Madison Matters-Ash Borer

The emerald ash borer, which has started showing up in southwestern, Ont., has been blamed for the loss of millions of trees across North America. (Minnesota Department of Natural Resources/The Associated Press)

A 2013 Canadian Forest Service report showed that it would cost the country as much as $2 billion over the next 30 years to cover the costs for treatment, removal or replacement of infected ash trees. 

The report also found that up to 98 per cent of ash trees die as a result of the pest within five years of infestation. 

The emerald ash borer has ravaged forests across the United States, after the beetle was discovered in Detroit, Michigan, in 2002.

The insects were shortly after found in Windsor.

With files from The Canadian Press