Elderberry Rust

Elderberry rust is a visually striking fungal disease that affects stems, leaves and flowers of plants in the genus Sambucus (i.e., elderberries). The disease also affects sedges (Carex spp.). On elderberries grown as ornamentals, as well as on sedges, the disease is primarily a cosmetic problem.

Phenology

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  5/17/2012 Item number:  XHT1085 The word phenology is derived from the Greek word phaino meaning “to show” or “to appear”.  Phenology is a branch of science that studies the relationships between periodic biological events—usually the life cycles of plants and animals—and environmental changes.  Natural events such as […]

Degree Day Calculation

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  8/6/2012 Item number:  XHT1086 Indicator plants are not always suitable for the timing of pest management practices.  You may not have the critical indicator plant  nearby to time local activities, or there may not be a good indicator plant for a particular pest’s crucial life stage.  Another […]

Boxwood Blight

Boxwood blight (also known as box blight and boxwood leaf drop) is a devastating disease of boxwood (Buxus spp.) that can cause leaf loss and eventual death of affected shrubs. This factsheet covers symptoms and management.

Eastern Filbert Blight

Eastern filbert blight is a potentially serious fungal disease found throughout the United States, including Wisconsin. It affects Corylus species, commonly known as hazelnuts or filberts, causing cankers on branches and trunks. Symptoms and management are described in this factsheet.

Cucumber Mosaic

Cucumber mosaic is a viral disease of worldwide distribution that affects over 1200 plant species. Hosts include a wide range of fruits, vegetables, herbaceous and woody ornamentals, and weeds. This factsheet covers identification and ways to prevent this incurable disease.

Black Knot, Apiosporina morbosa

Unsightly dark-colored lumps on plum trees are not only unattractive, but if there are lots of them, they can disfigure or even kill small trees. These swollen growths 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…

Verticillium Wilt of Trees and Shrubs

Verticillium wilt is a typically fatal disease that affects a wide range of deciduous woody ornamentals in Wisconsin. Trees most commonly and severely affected are maple and ash, but barberry, catalpa, elm, lilac, linden, smoke-tree and redbud are also susceptible. Symptoms and management are covered in this factsheet.

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