What Happened to All the Ash Trees in Niagara?
Most Ash trees were killed by Emerald Ash Borer (EAB).
What’s Actually Happening
Emerald Ash Borer (Agrilus planipennis) larvae bore into the bark and feed on the cambium — the tissue responsible for transporting water and nutrients. As the cambium is destroyed:
- Nutrient flow stops
- Canopies thin
- Trees die, often within a few years
EAB spread rapidly across Southern Ontario and devastated Ash populations. It has since spread further north.
Local Context (Niagara)
Niagara experienced widespread Ash loss. Some treated trees survived, but most untreated Ash were lost.
Emerging pests in Southern Ontario include:
- Spruce Adelgid / Sawfly
- Spongy Moth
- Spotted Lanternfly
- Hemlock Woolly Adelgid
How to Handle It
- Confirm species identification
- Monitor for new invasive pests
- Consider species diversity when replanting
Bottom Line
EAB reshaped Niagara’s canopy — and invasive pests continue to change it.