Maple Gall Mites (Eriophyidae)

Inside little green or red bumps or other weird growths on maple leaves are tiny eriophyid mites, feeding on the developing gall tissue. Learn more about these mites and what to do about them in this article on maple gall mites.

Chlorosis

Chlorosis is a common nutritional disorder of many woody ornamentals in Wisconsin, particularly in the southern and eastern parts of the state. This factsheet describes symptoms, causes and cures.

Oak Wilt

Oak wilt can be lethal, especially to oaks in red oak group. Learn about this disease of oaks, the life cycle and management options.

Powdery Mildew – Trees & Shrubs

Powdery mildew is a disease that occurs on the above-ground parts of many deciduous trees and shrubs, as well as herbaceous ornamental plants, indoor houseplants, and many agricultural crops. Learn more in this factsheet.

Anthracnose

Anthracnose is the name of several common fungal diseases that affect the foliage of woody ornamentals in Wisconsin. This factsheet describes symptoms and management.

Black Knot, Apiosporina morbosa

Large swollen dark-colored growths on plum and cherry trees are caused by a fungal pathogen that causes the disease known as black knot. To learn more about this disease and how to manage it, read this article.

Lichens

Lichens are organisms that arise from mutually beneficial interactions between certain fungi and algae. Learn about these harmless, and very common organisms in this factsheet.

Powdery Mildew Remedies

Powdery Mildew is a disease that affects a lot of different plants. On most plants, it’s harmless. Find out if various home remedies you’ve heard about are effective in this video!

Verticillium Wilt of Trees and Shrubs

Verticillium wilt is a typically fatal disease that affects a wide range of deciduous woody ornamentals in Wisconsin. Symptoms and management are covered in this factsheet.

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