They’re so tiny you can hardly see them but these little wasps may be the answer to saving the ash tree population in Ontario.

The federal government has approved the controlled release of two nearly identical species of wasp that feed on the eggs and larva of the emerald ash borer. The wasps do not have stingers and are around the size of a piece of sand.

The wasps come from China where they feed off the emerald ash borer.The hope is in time the wasps will put a significant dent in the emerald ash borer population to allow ash trees to survive.

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According to Barry Lyons, a forest entomologist with Natural Resources Canada, the wasps pose almost no threat to humans or our environment, “There is absolutely no potential impact on people or pets or anything other than emerald ash borer.”

The wasps, however, are not a quick fix. Lyons says it takes time to build up the population of the wasps before they can be effective,

“This is not a silver bullet, this is not something that happens overnight, it takes a long time to develop. In some areas in Ontario there are not a lot of ash trees that are surviving, so we are predicting that we won’t be able to save some of them, but maybe the next generation of ash tree that comes up,” he said.

The larva eating species has already been released in a few areas, but Natural Resources Canada recently began a larger release of both species of wasps. Wasp releases at locations near Tillsonburg, London and Georgetown are planned in the next couple months.