Distinguishing Oak Afflictions

Start Date/Time:

End Date/Time:

Oak trees (Quercus sp.) represent increasingly important components of the Michigan Landscape, whether the landscape is urban or is natural woodlands/forests. The loss of important species of trees (examples: Ash, Elm, and Chestnut), coupled with seemingly almost daily new introductions of pests and diseases (examples: Hemlock Wooly Adelgid, Beech Leaf Disease, Pear Trellis Rust), makes it vitally important that we learn to distinguish the myriad of Oak maladies so that we can properly manage and preserve this important genus of tree.

Some of the oak afflictions that may mimic one another or may be misdiagnosed include Anthracnose, Heat and Drought Stress, Cicada Damage, Physiological and Environmental Scorch, various Borers, Oak Wilt, and cultural problems such as herbicide misapplication and excess soil moisture that may lead to Phytophthora collar rot; both problems may result in tree death and be confused with Oak Wilt and other issues.

Dave Roberts

Dr. Dave Roberts

Dr. Dave Roberts has researched many issues in Michigan’s plant industry, including Oak Wilt, Dutch Elm Disease, and Diplodia Tip Blight of Pines, along with a variety of cultural problems such as plant nutrition and herbicide toxicity. During his career, he has discovered a variety of new diseases and pests such as Phomopsis Canker of Spruce and the first bacterial wilt disease of turfgrasses in North America. In the early 2000s, his research on Ash Decline in Southeast Michigan led to the discovery of the invasive Emerald Ash Borer in North America. 

In his retirement, Dr. Roberts intends to remain active with the Green Industry. Dr. Roberts is President, CEO and CBW (Chief Bottle Washer) of The Plant Doctor, LLC…aka the Tree Doctor.

The Plant Doctor, LLC