Diseases and Pests

Diseases and Pests

The Emerald Ash Borer is the predominant threat to Hudson's urban forest and is covered in detail on the Emerald Ash Borer (EAB) web page. Below are seven other tree disease and insect pests common in our area. They pose varying levels of risk and are listed in order of the significance of risk from greatest to least.

The Horticulture Division of UW Extension is the best web source for making an initial diagnosis of your tree problem. Onsite inspection by a qualified professional is recommended before any treatment is applied.

• Oak Wilt - Red and Pin Oak most at risk, bur, white, and bi-color low risk.  
• Japanese Beetle - Hosts are Linden, Crabapple, Birch, and Norway Maple.
• Bur Oak Blight - Threat to our oldest Bur Oak.
• Anthracnose - Cosmetic disease unless repeated attacks.
• Cytospora Canker - Colorado and Norway Spruce, Balsam, and Douglas fir.
• Verticillium Wilt - Severe damage to Maple and Ash
• Asian Longhorn Beetle - Attacks most all tree species BUT not here now.