Having lived in inner Toronto for many years, I have seen a lot of changes in the tree canopy of the city. When we first moved into our house over 15 years ago, the trees on our street were towering, some 2-3 feet in width and hanging over the street. But time has worn on, and the largest trees are slowly disappearing. Ice storms, improper pruning from utilities, poor maintenance – it’s surprising many have lasted as long as they have… but trees don’t last forever.
Below is what is left of an urban ash, clearly showing the drill lines where the city tried to prevent attack by ash borers by injecting insecticide – unfortunately it lost a major limb in the ice storm a few years back, and the wound was the catalyst in its demise. The brown staining is a consequence of the wound, which can apparently cause the stain to bleed through the whole trunk of the tree. The stain is not true heartwood, but rather a reaction to the wound, and any infection that occurs. It was only a matter of time.
More important though is to actually replace the tree canopy. Why isn’t there more effort spent on replacing the urban tree canopy?