Shade Trees Disorder: Decline, Dieback, or Early Senescence

Author(s): M.F. Heimann, G.L. Worf “Decline” is a general term that describes the deterioration of a tree’s crown or an overall reduction in vigor. “Dieback” indicates more localized symptoms, with healthy branches adjacent to dead or dying ones. Find out more about tree decline and dieback, how to spot the difference between the two, and […]

Deciduous Trees Disorder: Miscellaneous Causes of Decline

Author(s): G.L. Worf., J.E. Kuntz Many problems and disorders can lead to tree decline. This fact sheet explores sun scald, girdling roots, mower injury, previous defoliation, graft incompatibility, twine and tree wrap injury, and gas leaks as common causes of tree decline and death (4 pages). Click on this link to view the PDF of […]

Tar Spot of Trees and Shrubs

Authors: Brian Hudelson, UW-Madison Plant Pathology Last Revised: 12/17/2018 X-number: XHT1126 What is tar spot?   Tar spot is a common, visually distinctive and primarily cosmetic fungal leaf spot disease.  Tar spot can affect many species of maple, including (but not limited to) silver maple, sugar maple and Norway maple.  Boxelder (also known as ash-leaved maple), willow, holly and […]

Herbicide Damage

Brian Hudelson, UW-Madison Plant Pathology Revised:  5/11/2010 Item number:  XHT1004 What is herbicide damage?  Herbicide damage is any adverse, undesired effect on a plant that is caused by exposure of that plant to a pesticide designed for weed control (i.e., a herbicide).  Any plant can be subject to this problem. What does herbicide damage look […]

Woody Ornamentals Pest Management in Wisconsin

Author(s): Chris Williamson, P.J. Liesch, Jim Kerns, Roger Flashinski Woody Ornamentals Pest Management in Wisconsin is an indispensable resource for nursery growers. This completely revised publication identifies pests of trees and shrubs in the state plus the products available for their control. It also notes products that are registered for use by homeowners (56 pages; […]

Summer Flowering Trees, Shrubs and Vines

Laura Jull, UW-Madison Horticulture Revised:  8/13/2012 Item number:  XHT1016 May Showers Bring Summer Flowers: Most gardeners think that spring is the time of year when woody plants flower.  However, many trees and shrubs flower from late spring to late summer.  Wisconsin homeowners can choose from a variety of plants listed below to insure continual bloom […]

Oak Wilt

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:  8/13/2012 Item number:  XHT1075 What is oak wilt? Oak wilt is a lethal fungal disease that affects virtually all species of oaks.  Oaks in the red oak […]

Maple Gall Mites (Eriophyidae)

Have you found little green or red bumps or other weird growths on maple leaves and wondered what caused that? Inside each bump are tiny eriophyid mites, feeding on the developing gall tissue. If you want to learn more about these mites and what to do about this problem, check out this article on maple gall mites…

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