When we think of a healthy, sprawling forest, we often imagine a hands-off paradise where trees simply plant themselves and grow undisturbed. However, our woodlands face a constant influx of challenges. From unpredictable, severe weather events to invasive species and destructive fungi, maintaining the vitality of millions of acres requires constant vigilance.
The Michigan Department of Natural Resources (DNR) recently shed light on these very challenges, revealing that while the overall state of our greenery remains robust, localized threats require immediate attention. In particular, a perfect storm of recent weather damage and seasonal biology has put Northern and Northeast Michigan forests on high alert for a devastating tree disease: oak wilt.
Here is a look at what the latest data says about the health of Michigan’s forests and how you can help protect them this summer.
The Big Picture: Michigan’s Annual Forest Health Report
According to the DNR’s recently released Forest Health Highlights report, Michigan’s massive 20 million acres of forest (including nearly 4 million acres managed directly as state forest land) are generally in good health. However, certain areas are locked in tough battles against pests, diseases, and severe weather.
Foresters have their hands full addressing short- and long-term recovery efforts from a historic, catastrophic March 2025 ice storm. The storm triggered disaster declarations across 13 northern counties, snapping thousands of trees like toothpicks. On top of managing the literal fallout of these storms, the DNR’s specialized forest health team—consisting of foresters and invasive species biologists—worked tirelessly through 2025 to curb ecological threats. Their efforts included:
- Surveying 360 acres and treating 170 acres for hemlock woolly adelgid.
- Conducting aerial surveys across 18.2 million acres to map over 100,000 acres of localized canopy damage.
- Surveying 3,000 acres for high-risk invasive plants like cinnamon vine, stiltgrass, and lesser celandine.
- Treating 23 distinct oak wilt sites across the state.
The Summer Threat: Why Oak Wilt is a Growing Concern in 2026
While the DNR is tracking numerous pests like the balsam woolly adelgid and white pine needle diseases, local foresters and loggers are ringing the alarm bells about oak wilt as we head into the summer months.
As reported by WCMU Public Media, Northeast Michigan is uniquely vulnerable right now. The severe ice storms over the last two years have left many oak trees heavily damaged, stripped of their tops, or suffering from torn limbs.
Ben Nowakowski, an Alpena-based forester and logger, points out that high winds keep shifting the trees, preventing these storm wounds from properly healing. This creates an open door for infection during the peak oak wilt season.
How Oak Wilt Spreads
Oak wilt is an aggressive, fatal tree disease caused by a fungus. The high-risk infection window spans from mid-April to mid-July. During this time, small beetles are attracted to the fresh sap of open tree wounds. If these beetles carry the spores of the oak wilt fungus, they effectively inject the disease straight into the tree’s vascular system.
Once infected, an oak tree can rapidly lose its leaves and die in a single summer. If left unmanaged, the disease can spread to neighboring oaks through interconnected root systems, turning a single sick tree into acres of dead forest.
How You Can Help Protect Michigan’s Trees
Forest health experts emphasize that catching infestations early is the most effective way to limit the damage. “If you address them promptly while it’s small, it’s only a few trees,” Nowakowski told WCMU. “If you ignore it for five years, it’s many acres.”
Whether you are a private landowner, a backyard gardener, or an outdoor enthusiast hitting the trails this summer, here are the vital steps you need to take:
- Do Not Prune Oaks from Mid-April to Mid-July: Avoid any intentional trimming, pruning, or wounding of oak trees during this high-risk period.
- Paint Fresh Wounds Immediately: If an oak tree is accidentally damaged by a storm or equipment, immediately apply a tree wound dressing or latex-based paint to seal the wound and block sap-seeking beetles.
- Buy Firewood Where You Burn It: Transporting firewood is one of the fastest ways to introduce oak wilt and invasive pests to unaffected forests. Leave firewood at home and purchase logs locally at your camping destination.
- Watch the Canopy: Keep an eye out for hanging, broken limbs left over from past ice storms, which pose safety hazards on trails.
- Report Suspected Infections: If you notice a single oak tree rapidly wilting and dropping its leaves out of season, contact your local conservation district forester right away to have it assessed.
By staying informed and adapting our tree care habits, we can support the DNR’s ongoing conservation efforts and ensure that Michigan’s beautiful forests remain resilient for decades to come.
