What Happened To My Tree???

Trees add beauty, shade, and long-term value to your landscape - but like any living system, they can be vulnerable to disease. Many tree diseases begin quietly, showing subtle symptoms that are easy to overlook. Left untreated, those small warning signs can lead to weakened structure, declining health, and even tree loss.

Knowing how to identify common tree diseases early is one of the best ways to protect your landscape investment. Below are some of the most common tree diseases we see in southeastern Wisconsin, how they affect your trees, and what to watch for.

Rhizosphaera Needle Cast

Commonly affects: Spruce trees

Rhizosphaera Needle Cast is a fungal disease that slowly robs spruce trees of their needles, starting from the inside of the canopy and working outward. Over time, this leads to thinning branches, reduced growth, and stressed trees that become more susceptible to additional pests and diseases.

Signs to watch out for:

• Browning or purpling needles

• Needle loss starting from the lower and inner branches

• Sparse or thinning spruce trees

Diplodia Tip Blight

Commonly affects: Pine trees (especially Austrian and Scotch pine)

Diplodia Tip Blight attacks new growth, preventing proper needle development and stunting branch growth. Repeated infections weaken the tree's structure and appearance, often causing permanent damage if not managed early.

Signs to watch for:

• Brown, stunted new growth

• Resin-soaked buds

• Needles that fair to fully develop

Apple Scab

Commonly affects: Crabapple and apple trees

Apple Scab is a fungal disease that causes cosmetic damage at first, but repeated infections can significantly weaken trees over time. Severe cases lead to premature leaf drop, reduced flowering, and poor fruit production.

Signs to watch out for:

• Olive-green or dark spots on leaves

• Premature leaf drop

• Reduced flowering and fruiting

Oak Wilt

Commonly affects: Oak trees (especially red oaks)

Oak Wilt is one of the most aggressive and destructive tree diseases in Wisconsin. It interferes with the tree's ability to transport water and nutrients and can spread rapidly through root systems or insect activity. Without quick intervention, infected trees can decline and die within a single season.

Signs to watch out for:

• Leaf discoloration starting at the edges

• Sudden leaf drop during summer

• Rapid decline, especially in red oak species

Dutch Elm Disease

Commonly affects: Elm trees

Dutch Elm Disease is a spread by beetles and through connected root systems. Once infected, the tree's vascular system because blocked, preventing water movement and causing progressive branch dieback.

Signs to watch for:

• Wilting or yellowing leaves

• Branch dieback starting at the top

• Brown streaking beneath the bark

Chlorosis

Commonly affects: Maples, oaks, and other hardwoods

Chlorosis isn't a disease, but a nutrient deficiency - most often iron-related - that prevents trees from producing enough chlorophyll. While it may look harmless at first, untreated chlorosis can lead to poor growth and long-term stress.

Signs to watch for:

• Yellowing leaves with green veins

• Poor growth and thinning canopy

• Early leaf drop

How YPGA Can Help

Early detection and proper treatment are essential when it comes to managing tree diseases and maintaining a healthy landscape. Your Personal Gardener & Arborist offers comprehensive Plant Health Care services, including professional diseases diagnosis, targeted fungicide treatments, soil and nutrient managmeent, and long-term tree monitoring.

Whether you're noticing early warning signs or want to take a proactive approach to tree health, our experienced team creates customized treatment plans designed to protect your trees and prevent future issues.

Concerned about the health of your trees?

Contact YPGA today to schedule a Plant Health Care consultation and keep your landscape thriving for years to come.

https://www.ypgausa.com/contact