10 Signs of the Most Common Tree Diseases
blogdetail.jpg 29 May

10 Signs of the Most Common Tree Diseases

If you spot something strange on your trees, don’t panic! Like most living things, trees are susceptible to infections and infestations. While it may not be a major cause for concern, delaying treatment can cause severe damage or death. It is vital to familiarize yourself with the telltale signs of common diseases to prevent such scenarios and the subsequent yard damage of stump removal. The experts at Southern Star Stump can help you maintain healthy trees by scheduling routine inspections and care. Here are ten common tree diseases and the signs to look out for.

Leaf Rust

When you notice gold, orange, or reddish spots on the leaves, the tree is likely infected with leaf rust. Although the disease rarely kills plants, it affects aesthetics and photosynthesis. Each plant species is prone to rust fungus; in severe cases, the twigs can also be infected. The best solution is to conduct routine inspections and consult a local tree service for recommendations.

Fire Blight

Fire blight alters the appearance of trees and shrubs to look like portions of the branches have been scorched by fire. If you live in an area with warm moist weather, there’s a high chance of infection. Check the bark on the affected branches for a water-soaked, dry, or dark appearance and call a professional arborist for help. It is advisable to disinfect pruning tools and minimize the use of nitrogen fertilizers in spring and early summer. This goes a long way in preventing tree death and the cost of stump grinding.

Powdery Mildew

Mildew is a fungus that forms a white powdery coating on leaf surfaces during humid and dry weather. The disease usually affects trees growing in the shade, causing leaf distortion and overall tree deterioration. When planting trees in the backyard, we recommend planting resistant varieties like crabapples, crape myrtles, and lilacs. Several fungicides can control the spread of mildew, but consult an expert to ensure you choose the best option.


Gall is a common, unsightly fungal, or bacterial growth found on trees. It varies in size from 1/8 inch to massive swells on the trunk. Call a professional tree care company if you notice galls on leaves, shoots, or trunks of trees. Gall treatments vary depending on the cause, so we recommend hiring an expert.

Witches’ Broom

Trees infected with witches’ brooms develop odd-looking clusters of growth which resemble a broom. The infections can pop up all over your trees, causing irreversible damage and increasing susceptibility to infections. Pruning can help mitigate the spread of witches’ broom, but if you prefer a more hands-off approach, we recommend onboarding a professional. We can determine the severity of the damage and recommend fungicides to control the disease.


Canker occurs in dead areas on tree trunks or branches. It is caused by everything from environmental stress, such as sunscald and frost, to mechanical damage inflicted during construction or a lawn mower. Whether it is a small lesion on a branch, or a massive dead area on the trunk, delaying treatment can cause tree death and unplanned repairs following a stump removal job. Wrap young trees in the winter and remove dead or dying branches to prevent spreading.

Leaf Spot

Do you see reddish-brown spots in the foliage? This is often a sign of leaf spot disease, which spreads during the wet spring. The most vulnerable trees are ornamental cherry trees, but they can affect other species. Infected leaves easily drop off the tree, making detection easy. Tree pruning helps prevent the fungi from spreading and improves air circulation.

Japanese Beetle

Japanese beetles are notorious for feeding on leaves and flowers. Vulnerable trees include crabapple, linden, and birch. Another downside of these pests is that females lay eggs in the soil, which turns into grubs, wreaking havoc on your lawn. The best way to prevent a full-scale infestation is to plant trees the pests can’t feed on, such as hemlock, lilac, juniper, yew, and arborvitae.

Emerald Ash Borer (EAB)

The emerald ash borer is a metallic green insect which invades and kills ash trees. Common telltale signs of EAB include a thin or dying crown and irregular growth along the trunk. Dead growth is often a popular site for woodpeckers who hunt and feed on the beetles in the bark. There are many available treatments, and consulting an arborist can ensure you choose the right one.


Bagworms feed on the leaves of many shrubs and tree species. The larvae hatch in May or June and start feeding to construct a "bag", which turns into the entire body. Inspect trees regularly for signs of chewed leaves or defoliation on branches. In addition, check for two to three-inch bags hanging from the branches. If your trees are affected, spray Bacillus thuringiensis between May and June to kill young worms.

Call Southern Star Stump when you spot signs of infection or infestation. We leverage extensive knowledge and innovative equipment to ensure top-notch tree maintenance and stump grinding in Johns Creek, where necessary, at competitive rates.