The Temperature That Kills The Emerald Ash Borer
In many parts of the United States and Canada, the Emerald Ash Borer (EAB) has decimated millions (yes millions) of trees.
It kills the trees at the larval stage. The larvae tunnel around just under the bark, and these tunnels cut off the supply of nutrients to the tree and it dies.
All types of ash trees are affected and there have been reports of other tree varieties that have also been killed by the Emerald Ash Borer.
There are few natural defences to use against the Emerald Ash Borer though parasitic wasps have been said to help.
There was some hope that as the EAB migrated north that the cold temperatures would be able to stop it, but this now appears to not be the case.
In a paper published in 2018 about Emerald Ash Borer Death Temperature, the researchers concluded that:
"...most of North America does not experience extreme cold events frequently enough to prevent ash mortality from EAB (i.e., more frequently than every 6 years)..."
It would appear that the temperature that kills the Emerald Ash Borer is -35.4C, but this is the temperature that must be reached under the surface of the ash trees bark.
At a talk given in October 2019 by Brent Sinclair (one of the aforementioned paper's authors), he stipulated that the Emerald Ash Borer produces it's own glycerol which helps it to survive such extreme temperatures.
Even relatively cold cities like Winnipeg expect to lose most of their ash trees.
Here is another U.S. study that shows the mortality of the Emerald Ash borer due to cold temperatures.
So yeah, it's time to start planting more trees to replace the Ash NOW. The next questions is: "What Type?"...