Euonymus Scale

Phil Pellitteri, UW Insect Diagnostic Lab, UW-Extension Revised:  8/6/2012 Item number:  XHT1153 Euonymus scale is a non-native scale that attacks evergreen shrub and vine forms of Euonymus (e.g., wintercreeper).  In addition, this insect attacks privet, bittersweet and pachysandra. Appearance: Euonymus scale females grow up to 1/16 inch in length, are brown and are shaped like […]

Dutch Elm Disease

Jim Olis* and Brian Hudelson, UW-Madison Plant Pathology *Completed as partial fulfillment of the requirements for a BS in Plant Pathology at the University of Wisconsin Madison. Revised:  8/6/2012 Item number:  XHT1076 What is Dutch elm disease? Dutch elm disease is a lethal fungal disease of native North American elms.  The fungi that cause Dutch […]

Deciduous Tree Galls

R. Chris Williamson, UW Turf and Ornamental Specialist, UW-Extension Revised:  8/6/2012 Item number:  XHT1024 Galls are abnormal growths on plants that can result from the feeding of living organisms such as bacteria, fungi, nematodes, insects and mites.  There are numerous galls that are caused by insects, the most common of which, in Wisconsin, are ash […]

Chlorosis

Brian Hudelson, UW-Madison Plant Pathology, UW-Extension Revised:  1/8/2012 Item number:  XHT1002 What is chlorosis?  Chlorosis is a common nutritional disorder of many woody ornamentals in Wisconsin, particularly in the southern and eastern parts of the state.  Pin oaks are most commonly affected by chlorosis, although many other trees and shrubs (e.g., white oak, red maple, […]

Gymnosporangium Rusts

Authors: Brian Hudelson, UW-Madison Plant Pathology Last Revised: 01/23/2019 X-number: XHT1009 What are Gymnosporangium rusts? Gymnosporangium rusts are a group of closely related diseases caused by fungi that infect both junipers (in particular red cedar) and woody plants in the rose family (such as, but not limited to, apple, crabapple, hawthorn and quince). These fungi […]

Planning and Designing Your Home Landscape

Dan A. Wilson, Thomas J. Wilson, Wayne G. Tlusty Revised:  5/10/2010 Item number:  G1923 This publication explores landscape planning: putting the plan on paper; selecting, placing, and planting trees and shrubs; and maintaining the home grounds. Download Article

Home Landscape Insecticides

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  8/13/2012 Item number:  XHT1096 Recently, several commonly-used insecticides for the control of insects on woody landscape plants have been taken off the market.  As a result, it’s becoming ever more challenging for home gardeners to find suitable insecticide products at garden centers, discount stores, and hardware stores.  […]

Pruning Deciduous Trees

Laura Jull, UW-Madison Horticulture, UW-Extension Revised:  8/13/2012 Item number:  XHT1014 Why prune trees? Pruning is important for a variety of reasons.  Pruning can help control the size of a tree, direct growth, influence flowering or fruiting, or maintain plant health and appearance.  Pruning can also increase the safety of a tree by removing broken, diseased, […]

Boxelder Bugs

Rebecca Hoffman*, UW-Entomology and Phil Pellitteri, UW Insect Diagnostic Lab Revised:  5/7/2010 Item number:  XHT1100 Boxelder bugs, a true bug from the insect family Rhopalidae, are commonly found both outside and inside homes during the fall through early spring. Boxelder bugs are about 3⁄4 of an inch long, and black in color with three red […]

Black Walnut Toxicity

Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Revised:  5/7/2010 Item number:  XHT1017 What is black walnut toxicity? Black walnut trees (Juglans nigra) produce a toxic substance (called juglone) that prevents many plants from growing under or near them. Related trees like butternut (J. cinerea) and shagbark hickory (Carya ovata) also produce juglone, but in […]

Ash Flower Gall

Phil Pellitteri, UW Insect Diagnostic Lab, UW-Extension Revised:  8/6/2012 Item number:  XHT1048 What is wrong with my ash tree?  Galls are abnormal plant growth that can be caused by insects, mites or plant diseases.  On ash trees, a tiny eriophyid mite causes male flowers to grow into round greenish, 1∕2 to 1 inch diameter tumor-like […]

Bacterial Blight

Gina Foreman* and Brian Hudelson, UW-Madison Plant Pathology *Completed as partial fulfillment of the requirements for Plant Pathology 875 – Plant Disease Diagnostics Clinic Internship at the University of Wisconsin Madison. Revised:  4/25/2004 Item number:  XHT1093 What is bacterial blight?  Bacterial blight, also known as blossom blight or shoot blight, is a common and often […]

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