Spring and summer are prime growing seasons for trees—but they’re also the peak time for many common tree diseases to take hold. Warmer weather and increased humidity create the perfect environment for fungal tree infections, pests, and other stressors that can compromise the health of your trees. Early tree disease identification is crucial to preventing long-term damage or tree loss. Here’s what to look for, how to prevent issues, and when to seek professional tree health services.
Sick Tree Symptoms: What to Watch For
If your tree doesn’t look quite right, trust your instincts—there are several visible signs that may indicate disease or stress. Keep an eye out for these sick tree symptoms:
- Discolored or spotted leaves: Yellowing, browning, or speckled leaves may point to fungal infections or nutrient deficiencies.
- Early leaf drop: If your tree is shedding leaves well before fall, that’s often a stress signal.
- Cankers and oozing bark: Sunken areas, cracks, or sap seepage may indicate bacterial or fungal pathogens.
- Wilting foliage or branch dieback: Especially in the spring or early summer, this could mean root disease or vascular blockage.
- Mold, mildew, or fungal growth: Powdery or fuzzy substances on leaves, branches, or bark are signs of active infection.
- Presence of insects or exit holes: Boring insects can be both a cause and a symptom of tree decline.
These symptoms can be subtle at first, which is why routine monitoring is key to maintaining healthy trees.
Common Tree Diseases in Spring and Summer
Many diseases become active or visible during the growing season. Some of the most common tree diseases to watch for in Illinois include:
- Anthracnose: A fungal infection causing leaf blotches, curling, and early leaf drop—often seen in ash, oak, and sycamore trees.
- Apple Scab: Targets crabapple trees, causing olive-green lesions on leaves and fruit.
- Powdery Mildew: Appears as a white or gray film on foliage and thrives in warm, dry conditions.
- Verticillium Wilt: A soil-borne fungus that affects maple and other hardwoods, leading to wilting and branch dieback.
- Cedar-Apple Rust: Appears as orange spots on apple and crabapple trees and can cycle between junipers and rosaceous hosts.
While some issues are primarily cosmetic, others can significantly weaken or even kill the tree if left untreated.
Tree Disease Prevention Tips
The best approach to managing tree diseases is proactive care. Follow these tree disease prevention tips to keep your landscape healthy:
- Choose disease-resistant varieties when planting new trees.
- Water deeply but infrequently to avoid waterlogging the roots, especially during dry spells.
- Mulch properly to retain moisture and reduce temperature fluctuations—but don’t pile mulch against the trunk.
- Prune during the dormant season to remove dead or diseased limbs and improve airflow.
- Avoid wounding the tree, which can invite pathogens.
- Regular inspections by certified arborists can catch problems early.
When to Call a Professional
While DIY methods can help in some cases, there are times when professional help is necessary. If you notice persistent symptoms, rapidly declining health, or suspected pest infestations, it’s time to bring in the experts. A professional arborist can provide accurate tree disease identification and recommend effective tree health services, including fungicide treatments, tree pest control, root zone therapy, or pruning.
In some cases, what looks like a disease might actually be a pest issue or environmental stress. Professionals have the diagnostic tools and experience to determine the root cause and apply the right treatment plan.
Keep Your Trees Healthy with Homer Tree Care
Don’t let tree diseases take root in your yard this season. At Homer Tree Care, our team of certified arborists offers expert tree health services, from diagnosis and treatment to long-term care. Whether it’s fungal tree infections, pests, or mystery symptoms, we’re here to help protect your landscape investment.
If you’re concerned about your trees or want to schedule a preventative check-up, contact us today for a free consultation. Let us help you stop the spread before it starts!