Identifying Oak Wilt In Toronto: Oak tree’s significance in the Toronto community goes beyond its thriving urban forests— it is also the city’s official tree.
Yet not even this city symbol is safe from the invasive oak wilt, a disease that can kill an oak tree in a single season.
Now that it has been detected in Springwater and Niagara Falls, the government is making efforts to protect the local oaks. But Toronto residents and tree owners must also come together to help combat the oak wilt.
Here’s a guide from expert arborists so you can learn more about this damaging tree disease and how to spot its symptoms.
What is Oak Wilt?
Oak wilt is a vascular disease found in oak trees that are infected by the fungus Bretziella fagacearum.
The fungus grows on the oak’s outer sapwood and clogs the xylem which delivers water and nutrients to the different parts of the tree.
Deprived of its needs, infected trees may die in as fast as a few weeks. It will also spread the fungal spores to other healthy trees, unless intervened with.
The rate of the tree’s death largely depends on the tree species. Trees from the red oak group may die in just weeks or a few months, while those in the white oak group can live and carry the disease for years.
With the kind of damage it does to both natural and urban forests, you can rely on your local arborists to take action and stop its spread.
Heritage Tree Care’s team of ISA-certified arborists will do damage control on the oak wilt fungus, following the proper procedures to stop its further spread.
Signs of Oak Wilt in Toronto
Recognizing this fungal disease at its onset is crucial to prevent the threat of oak wilt spread in Toronto.
But what does oak wilt look like? As this dreaded tree disease does its dirty job to your tree’s vascular system, trunk and leaf symptoms will begin to appear.
Leaf Bronzing
The lack of water and nutrients causes the wilting of the leaves. You will see them turn brown or yellow from the leaf tip and margins towards the midvein.
The discoloration of the leaves will crawl until they color whole branches. This begins from the top of the tree and moves downward— enveloping your oak’s canopy.
Premature Shedding of Leaves
If leaves fall when they’re not supposed to yet, then the oak wilt fungus may be the culprit.
When you inspect the fallen leaves and they exhibit the bronzing symptom, the odds that your tree has oak wilt disease becomes even more likely.
The Bark Cracking
As the fungus gets comfortable underneath the infected wood, fungal spore mats will produce pressure pads that can crack the bark open.
This bark-breaking feat unleashes a scent that attracts the sap-feeding beetles— then the same sap beetles will carry the oak wilt spores to other trees.
Brown Streaks in The Outer Sapwood
When you look closely at the outer growth rings of your oak, you may also see some brown streaks in there. This symptom of oak wilt is mostly seen in red oak trees, while the white species of oaks may not show it at all.
Need assistance in identifying oak wilt? You can contact Heritage Tree Care and connect with our tree experts for a consultation.
The Spread of Oak Wilt
Once an oak wilt center has been established in an infected tree, it will continue to spread especially if it’s in close proximity to other oaks.
The fungal spores usually enter through fresh wounds with the help of the sap-feeding Nitidulid beetles. Strong winds and water can also deliver the disease to wounded trees.
The fungus can also travel underground through the tree root grafts. The root connections serve as bridges for the fungus to move from one tree to another.
Tips to Prevent Oak Wilt Spread
Tree owners have a significant role to play in protecting Toronto’s precious oaks. From a single infected tree, oak wilt can spread fast; leaving a path of dead trees in its wake.
So don’t let it thrive without a fight. There are ways to reduce your oak tree’s vulnerability to this disease:
- Never prune oaks between April and July. This is when the spore-carrying insects are most active, so giving your oak tree open wounds during this time can be fatal.
- If your oak tree already has open wounds or fresh cuts, you can cover them with pruning seals or paint. These will mask the scent that attracts the beetles.
- Get fungicide macro-injection treatments from your local tree service company. The fungicide can help protect your tree from any unwanted oak wilt breach. It can also slow down the progress of an already infected tree.
- Leave the tree removal to the professionals. Cutting down a tree with oak wilt requires extra care to avoid getting the spores all over the place. This also involves trenching which severs the root grafts so nearby trees will no longer catch the disease.
Hire a Professional
Heritage Tree Care is your trusted tree care company in Toronto. We make it our mission to help maintain the city’s prized urban forests, so we take invasive threats like oak wilt seriously.
The International Society of Arboriculture certifies our tree specialists, and they have the skills, knowledge, and equipment to combat oak wilt’s potential harm in our city.