
By P.A.Sévigny
As of last week, the Coderre administration is now beginning to use Tetrastichus Planipenisi – a tiny Asian wasp – as their newest weapon against Agrilus Planipennis – the city’s ubiquitous Emerald Ash borer. If left unchecked, the ash borer is the invasive species that will completely transform the city’s massive centuries old green canopy as it continues to threaten more than 400 000 of the city’s ash trees to a slow but certain death. As described in previous Suburban reports, the emerald ash borer is the bright green beetle that’s originally native to Asia and eastern Russia. As a result of our globalized economy, the invasive species was accidentally imported into North America after which it didn’t take more than a few years before the beetle become a major threat to all of the continent’s ash trees in much the same way as it took little more than a generation before the Dutch elm disease killed all but a few of the continent’s elm trees.
Following several multi-million dollar efforts to deal (and eradicate) the noxious beetle that were as expensive as they were inconclusive, the city recently decided to import the beetle’s natural enemy in order to control, and effectively destroy the invasive beetle’s life-cycle in North America. Citing a working protocol that sounds as if it was lifted off the pages of Alien – the vintage horror movie, Maryse Barrette, a city environment department employee, described how the Asian wasp’s parasitical life cycle could effectively decimate and eventually eradicate the emerald ash borer from all of North America.
As of last week, city employees began to install a number of birch logs that were already infested with the asian wasp’s eggs near some infested trees after which they will eventually hatch, fly away and find the ash borer’s larvae that they specifically need to begin a new life cycle for their own species. As each and every one of the borer’s larvae can support up to 130 pupae that will slowly feed off and kill the beetle’s larvae before they become mature wasps, Barrette believes that it’s only a matter of time before the wasp’s numbers overwhelm the beetle’s population in time to save the city’s ash trees. As the wasp does not sting and is no bigger than your average fruit fly, the city has nothing to fear because after millions of years of sustained evolution, it only attacks the emerald ash borer after which the wasp’s existence is only threatened when it has effectively wiped out the insect population it needs to survive and to propagate its own species.
While it’s not the first time the tiny wasp has been used as an attempt to control the spread of the invasive beetle, it is the first time that the new bio-weapon is being used in a densely populated urban area. As the USDA (United States Department of Agriculture) and the Canadian Forest Service are responsible for the initial research behind the new bio – weapon, the USDA has already agreed to supply several thousand wasp eggs at no cost in return for such information as the city can gather about their effective use within an urban environment. Although it’s going to take several years before anyone will be able to know whether the new program is a success, Barrette did say that the spread of the Asian wasp has already reduced the spread of the emerald ash borer in the northern United States and elsewhere in southern Ontario.