Root-Knot Nematode

Root-knot nematodes are small, soilborne, worm-like organisms that infect many agricultural and horticultural plants. This publication describes the symptoms, and management of root-knot nematodes in Wisconsin.

Foliar Nematodes

Foliar nematodes are microscopic worm-like organisms that live in and on leaves (and other above-ground plants parts). Learn what to look for and how to manage foliar nematodes in this factsheet.

Brown Rot

Brown rot is a destructive fungal disease of the genus Prunus, including plums, cherries, apricots, and peaches. This factsheet will help you identify and manage brown rot.

Nectria Canker

Nectria canker is a common and potentially lethal disease that affects many species of trees and shrubs. This factsheet describes what nectria canker looks like and management options.

Southern Blight

Southern blight is a lethal fungal disease that is most common in the tropics and subtropics, but can cause problems in temperate locations like Wisconsin during periods of warm, moist weather. Learn more here.

Plum Pox

Plum pox, aka “sharka”, is a virus disease that affects stone fruits such as plums, peaches, apricots and nectarines, making fruit deformed, tasteless and inedible. Learn about symptoms and management here.

Crown Gall

Crown gall is the most widely distributed bacterial disease of plants in the world. This factsheet describes what crown gall looks like and how to avoid problems with this disease.

Dead Man’s Fingers

Dead man’s fingers is the name of a mushroom-like fungal growth that can be found at the base of dead or dying trees and shrubs, as well as wood objects. Learn about this distinctive fungus in this factsheet.

Bitter Pit and Cork Spot

Bitter pit and cork spot are common disorders of Wisconsin apples, when weather conditions are just right. This factsheet describes what can be done to reduce the severity.

Bacterial Canker

Bacterial canker is a common and sometimes lethal disease of trees in the genus Prunus including cherry, plum and peach. This factsheet describes symptoms and management of bacterial canker.

Peach Leaf Curl

Peach leaf curl is a common disese of peach and nectarine trees, and can reduce tree vigor, fruit quality and yield. Learn symptoms and management options in this factsheet.

Fire Blight

Fire blight is the most destructive bacterial disease affecting plants in the rose family, including apple, pear, crabapple, hawthorn, cotoneaster, mountain ash, quince, rose, pyracantha, and spirea. Learn more here.

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