Emerald Ash Borer is the most damaging pest introduced to our forests since Dutch Elm Disease in the 60’s and 70’s. It’s a beetle that hitchhiked here from Asia and has set to devouring ash trees since it was first found in Windsor and Detroit in 2002. It feeds on the inner bark of all species of ash trees and in every case will kill that tree within a few years of first attack. There is no genetic resistance to the beetle and there are no natural predators that can control its spread.
Now that the doom and gloom is over with, let’s get to reality. Urban forests are a vital component of our city. Their canopies that spread throughout our neighbourhoods return tangible and intangible values that cannot be easily replaced or engineered. We need trees, and lots of them in our cities to give us shade and clean air but most importantly, we need them to make our city livable.
The EAB presents a big problem for our urban forest: we have dozens of streets lined with 100% mature ash trees. We have beloved ash trees in back yards and front yards all over the city, tire swings hanging from limbs and all. It is not necessary to submit to defeat and let all of our ash trees die, we can intervene. Affordably and responsibly.
We have some tools to fight against EAB, they’re limited but effective. We can inject our trees with a couple choices of pesticide to protect them from attack and keep them alive as long as we’re able to keep up with treatments every year or two. It’s not cheap, but it’s much cheaper than removal, stump grinding and replacement. Incredibly cheaper if you factor in the dollar value of what a street tree gives us in return.
The decision to intervene couldn’t be simpler on the surface: inject now for a bit of outlay regularly over time or don’t inject and bear the cost of removal and replacement. Where that decision gets more difficult is when it has to be made for a large group of trees, whether it be 10’s of trees or 1000’s of trees. Regardless of the decision, there will be a significant cost, it’s entirely unavoidable.
For a large group of trees (ie. a forest…), it’s most responsible to pick the highest value, strongest, healthiest, largest trees and invest in their protection. The rest are removed and replaced in as long a time period as possible. If this process isn’t planned well in advance, the EAB will spread quickly like wildfire and the cost burden of removal and replacement will be painfully concentrated over just a few years. Not to mention the safety risk of a proliferation of dead trees throughout our city!
Thunder Bay is well positioned to handle this. We’ve known about EAB for years and we’ve been planning for it actively. Now that it’s here we need to act on good planning and be proactive about protecting our best trees so that we can avoid the financial and social pain of losing all our ash trees quickly and suddenly.