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.

Lilacs for Cold Climates

Learn about the best-rated lilacs for Wisconsin’s cold climate, and how to care for these plants for years of enjoyment.

Degree Day Calculation

Degree Days incorporate temperature and time to quantify the rate of plant and insect development. This useful tool helps predict events such as flowering, harvest, and pest outbreaks.

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.


Phenology is a branch of science that studies the life cycles of plants and animals with seasonal changes and weather. Learn more in this factsheet.

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.

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