Jerzy Opioa/ Wikimedia Commons /CC BY-SA 4.0
Not all species are susceptible to all tree fungus diseases.
Plus, not every tree fungus is fatal.
Sometimes they merely mar a tree’s appearance.
Jerzy Opioła/ Wikimedia Commons /CC BY-SA 4.0
In cases where they are fatal, however, treatment is essential because a tree represents a substantial investment.
When in doubt,consult an arborist.
Fungal diseases move around via spores, and spores spread in a variety of ways.
Ingwik/ Wikimedia Commons /CC BY-SA 4.0
Sometimes, there’s nothing you’re free to do about the spread.
Insects can bring spores with them, or spores can be spread by the elements.
Spores traveling on the wind arrive no matter what you do.
Wood Geek/ Wikimedia Commons /CC BY-SA 4.0
Other times, though, spore spread is entirely within your control.
Spores can spread through improper irrigation, on gardening tools, and from your own body to susceptible trees.
In these instances, you might prevent spore spread.
USDA Forest Service / Wikimedia Commons /CC BY 3.0
Indeed, prevention is generally the answer to tree fungal issues.
Disinfect tools, avoid contact with plants on wet days, and don’t over-water.
Dutch Elm Disease
Ingwik/ Wikimedia Commons /CC BY-SA 4.0
Fungal diseases are grouped into categories.
Jerzy Opioła/ Wikimedia Commons /CC BY-SA 4.0
The fatalDutch elm diseasefalls into the “wilt” category.
These fungi attack the vascular system.
When its vascular system is weakened, your tree develops problems circulating water and nutrients.
CoolKoon/ Wikimedia Commons /CC BY-SA 4.0
The fungus behind it is spread by elm-bark beetles.
Signs that anelm treehas it show up in the foliage.
The leaves can curl, drop, wilt and turn yellow.
Amnon Shavit/ Wikimedia Commons /CC BY-SA 3.0
Growing resistant cultivars is the best option as treatment is difficult.
This tree fungus is spread by sap beetles.
The fungi responsible are soil-borne.
Clemson University / Wikimedia Commons /CC BY 3.0
Trees with this fungus experience curling, drying up, and yellowing of leaves.
Slow growth is another sign.
No fungicide kills this.
Forest and Kim Starr/ Wikimedia Commons /CC BY 2.0
Your only option is prevention.
The best step to take is growing a tree not susceptible to it, likearborvitae(Thuja spp.)
orbirch(Betula spp.).
Holger Krisp/ Wikimedia Commons /CC BY 3.0
Powdery Mildew
Other fungal diseases fall into the foliar-disease category.
Here, the fungal spores attack the leaves directly.
Perennials liketall garden phlox(Phlox paniculata)commonly get it, but trees get it too.
To prevent it, space plants properly (promoting air circulation) and practice sound irrigation policies.
This leads to misidentification, as it looks like insects could have caused the damage.
By mid-summer, the leaves turn yellow and drop.
Helpfully, several fungicides can be used as treatment.
It takes the form of a black film covering the leaves.
Scale insects are ultimately responsible for the presence of sooty mold.
Control these insects withneem oil, and you won’t have trouble with this tree fungus.
An infected tree suffers dieback eventually.
Prior to that, you’ll notice blotches and wilting on the leaves.
Like many fungi, it’s especially active in spring.
It’s harbored in winter by leaves you allowed to stay on the ground from last year.
Raking up those leaves and taking them elsewhere is the simple solution.
Trees stressed for too long by this disease become susceptible to insect infestations.
Dogwood(Cornus spp.)
is one of the popular trees that’s highly susceptible to this fungus, which is fatal.
As more spots appear, leaves become unable to carry out photosynthesis, and overall tree health suffers.
Several fungicides are available for treatment.
Various fungi are responsible for root rot, includingPhytophthoraandArmillaria.
Root rot is fatal.
Although the presence ofArmillariais sometimes indicated by mushrooms, don’t rely on mushrooms as an indicator.
The best way to treat most fungi is to call an arborist.
It’s tricky even for pros to be able to identify fungi without sending samples to the lab.
Remember that the parts of the fungus you’re able to see is just the fruiting body.
If it’s not flowering, there is no way to identify it without a lab.
