Fungus growing on your tree can be both harmful and beneficial, depending on the type of fungus. Fungi are living organisms that have eukaryotic cells which are responsible for breaking down organic matter, and releasing oxygen, nitrogen, carbon, and phosphorous into the surrounding soil and atmosphere.

Mushrooms are an external indicators that a tree fungus has already invaded the internal network of the tree and has started consuming the tree from the inside. We’ll go over the main types of tree fungus, how they affect your trees, and what treatment options are available.

a diseased tree covered in tree fungus
a diseases tree with a tree fungus


Fungal Foliar Diseases:

Foliar diseases are caused by a type of fungi that attack the leaves of the tree.

Canker Diseases:

Canker diseases are often caused by improper pruning and involve a type of fungi that enter the tree through wounded sections of bark of branches.

Wilt Diseases:

Wilt diseases are caused by a strain of fungi that invades a tree’s vascular system and compromises the trees ability to adequately transport water and nutrients throughout itself.

Some symptoms of a fungal invasion might be easy to miss until there are physical symptoms like mushrooms growing on the tree, at which point it might be too late to treat your tree. That’s why it’s important to rely on a certified arborist to provide a thorough examination of your tree to better help identify and treat the presence of tree fungus.

Our Ottawa arborists are experienced in arboriculture and know how to identify damage before mushrooms appear. If you’re unsure whether you tree has a tree fungus, give us a call and we’ll help you get to the root of the problem.


Black Knot

Black not is a type of fungus that invades trees in the genus “Prunus”. It is a slow developer that takes roughly a year to develop until it becomes visually apparent and starts to produce spores. Once Black Knot is established, it can be easily identified because of the black galls that it creates on the tree. It’s important to control the infection at its earliest point to increase the survival of the tree. Our certified arborists are trained to be able to identify the presence of Black Knot fungus early on and to provide a treatment to prune the affected areas. If left untreated, Black Knot can severely deteriorate the health of your tree, it can spread to other trees on your property, and it can result in the death of your tree.

Read our blog: What is Black Knot Fungus? How Do You Treat It?

Dutch Elm Disease

The fatal Dutch Elm Disease falls into the “wilt” category of tree fungus diseases. The specific type of fungus associated with Dutch Elm Disease attack the vascular system of the tree, impeding the ability of your tree to circulate water and nutrients. The fungus is primarily spread by the infamous elm-bark beetles. If the leaves on your elm tree are wilting and starting to turn yellow, it’s time to take action. For a professional examination of your tree and to treat the presence of Dutch Elm Disease, call on the certified arborists at Croft Tree Experts.

a tree with black knot fungus
a certified arborist inspecting a tree for the presence of a tree fungus


First and foremost, our goal is to identify the disease that might be plaguing your trees and to determine whether or not we can save your trees. The treatment options available will depend on the severity of the fungal infestation and the type of fungus present. If your tree can’t be saved, it will have to be removed for the sake of reducing the spread of the disease and to save the other trees on your property.

Our trained team of arborists are equipped with the tools, experience, and training to evaluate tree fungus and diseases in order to recommend the appropriate course of action. Contact us today!

Our Arborist Services

We employ certified arborists who have passed comprehensive and regularly repeating exams developed by some of the nation’s leading experts on tree care. An arborist is an individual who is trained in caring for, planting, and maintaining trees.

When you hire Croft Tree Experts to remove a tree in Ottawa, you're getting the services of a certified arborist on staff. That's how we ensure that we're removing your tree safely as well as within compliance of Ottawa tree permit bylaws.

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Contact Us

Get in touch with Croft Tree Services today! We’ll answer any questions you may have, and work with you to find the right solution and the most convenient scheduling options for your tree and landscaping needs. Please be as specific as possible in the field below, so that we can help you in the most effective way.


    208 Royalton Private
    Ottawa, ON K1V 9S3

    (613) 883 5611 or  (613) 410 4677


    Monday to Friday: 8am to 6pm
    Saturday: 9am to 3pm
    Sunday: Closed