Black Vine Weevil

R. Chris Williamson, UW-Extension Turf and Ornamental Specialist Revised:  8/13/2012 Item number:  XHT1065 The black vine weevil was first detected in Connecticut in 1910, and was reported to have been accidentally imported from Europe through the movement of ornamental plants. Subsequently, it has spread across the northern U.S., including Wisconsin. There is a closely related […]

Winter Salt Injury and Salt-tolerant Landscape Plants

Laura Jull, UW-Extension Revised:  8/13/2012 Item number:  A3877 This publication focuses on recognizing and preventing plant damage caused by deicing salts, evaluates the pros and cons of alternatives to rock salt, and provides an extensive list of salt-tolerant plants.   Download Article

Conifer Disease Quick Reference

Authors: Brian Hudelson, UW-Madison Plant PathologyLast Revised: 04/30/2021D-number: XHT1025 Root and Crown Rots Hosts: All conifers Pathogens: Pythium spp., Phytophthora spp., Rhizoctonia solani, Fusarium spp., Cylindrocarpon spp. Signs/Symptoms:  Poor growth, branch dieback, discolored and deteriorated roots For more information see: UW Garden Facts XHT1070   Rhizosphaera Needle Cast Hosts: Colorado blue spruce, other spruces, many other conifers Pathogen: Rhizosphaera kalkhoffii Signs/Symptoms:  Browning/purpling of interior needles of lower branches, followed by needle drop For more […]

Proper Tree Planting Techniques (B&B)

Vijai Pandian, Horticulture Educator, Brown County UW-Extension Revised:  8/13/2012 Adopting proper tree planting techniques ensures long survival and good health of your trees. This publication is intended to guide homeowners, landscapers and individuals through the steps of proper tree planting techniques. This brochure shows you how to correctly plant balled and burlapped trees and shrubs.   Download […]

Powdery Mildew – Trees & Shrubs

Brian Hudelson, UW-Madison Plant Pathology Revised:  8/13/2012 Item number:  XHT1005a What is powdery mildew?  Powdery mildew is a disease that occurs on the above-ground parts (especially the leaves) of many deciduous trees and shrubs, as well as herbaceous ornamental plants, indoor houseplants, and many agricultural crops.  Conifers are not affected by this disease.   What […]

Fire Blight

Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Revised:  4/24/2004 Item number:  XHT1090 What is 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.  It can kill or disfigure a tree or shrub, depending on […]

Downy Mildew

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:  XHT1077 What is downy mildew? The downy mildews are a group of fungal diseases that cause destruction of the leaves, stems, flowers and fruits […]

Bacterial Wetwood

Mary Francis Heimann, O.S.F., Distinguished Outreach Specialist emerita at the University of Wisconsin-Madison and Brian Hudelson, UW-Madison Plant Pathology Revised:  8/13/2012 Item number:  XHT1193 What is bacterial wetwood? Bacterial wetwood, also known as “slime flux”, is a visually frightening-looking, but typically non-lethal, disorder of many types of deciduous trees. This disorder can reduce the aesthetic […]

Apple Scab

Brian Hudelson, UW-Madison Plant Pathology Revised:  11/19/2018 Item number:  XHT1007 What is apple scab?  Apple scab is a potentially serious fungal disease of ornamental and fruit trees in the rose family.  Trees that are most commonly and severely affected include crabapple, hawthorn, mountain-ash, apple and pear.  In ornamental trees, leaf loss caused by apple scab […]

Top Ornamental Crabapples for Wisconsin

Laura Jull, UW-Horticulture Revised:  8/13/2012 Item number:  XHT1012 Why grow crabapples? Ornamental crabapples are very popular, small to medium-sized ornamental trees suitable for urban environments. There are more than 650 different cultivars of crabapples with a variety of leaf, flower, and fruit colors, fruit sizes, and growth forms. Crabapples are tolerant to a wide range […]

Plants Not Favored by Deer

If deer visit your property, you’ve likely already experienced the frustration of having landscape plants destroyed overnight. Before planting (or replanting), check out this list of trees, shrubs, flowers, herbs, and grasses that deer tend to avoid.

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