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.

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.

Root Rots in the Garden

Root rot is a general term that describes any disease where the causal organism attacks and leads to the deterioration of a plant’s root system. Learn about root roots and their management in this factsheet.

Elderberry Rust

Elderberry rust is a visually striking cosmetic fungal disease that affects stems, leaves and flowers of plants in the genus Sambucus (i.e., elderberries), and also affects sedges (Carex spp.). Learn more in this factsheet.

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