WINNIPEG -- The number of ash trees infested with emerald ash borer in Winnipeg is growing and the beetle which burrows under bark has been found kilometers from where it was initially discovered.

Fifteen infested trees in the city have been confirmed. Thirteen of them were identified in the Archwoord area in 2018. Another two have since been discovered on Marion Street.

The beetle is also on the move. The City of Winnipeg said in summer 2018 an adult beetle was found as part of its monitoring program in Windsor Park, five kilometres from the Archwood where the infestation was first detected.

“We can confirm that the population is dispersing to other areas of the city. Our forestry staff continue to be vigilant when working in any part of the city," said communications officer Ken Allen in an email to CTV News, noting the emerald ash borer can be transported through the movement of firewood.

The city said to slow the spread of the beetle it has injected about 1100 ash trees with insecticides to help give them temporary protection.

Another 1,000 trees will be treated this summer.

“This injection program is designed to spread out tree removals over a longer period of time to help keep the tree removal work manageable – but these injections are not being used to protect the trees indefinitely,” said Allen.

The city estimated in 2018 there are more than 350,000 ash trees on private and public property in Winnipeg.

New firewood rules

The city said Winnipeg has been designated as a regulated area by the Canadian Food Inspection Agency, which means transporting any type of firewood from Winnipeg is no longer allowed.

“If you’re going to the cabin or campground, please leave your firewood at home and buy new firewood when you get there,” Allen said.

The city reminds everyone the most important thing that can be done to help slow the spread of emerald ash borer is to not transport firewood and burn it where it’s purchased.

Increasing tree diversity

The city it is working to gradually replace many ash trees with other species to increase tree diversity and a number of ash trees are being removed.

“For example, we are removing many dead and dying ash trees in River Heights and Riverview neighbourhoods due to the damage caused by another invasive pest - cottony ash psyllid (also known as 'jumping tree lice'). Replacement of these trees is scheduled to take place within the next two years,” Allen said.