Learn if your property is at risk, how to reduce the spread of oak wilt in a forested area, how to know if a tree has oak wilt and much more.
Distribution
Oak wilt is widespread in southern Wisconsin, but in much of northern Wisconsin it is…
European spongy moths were accidentally introduced into Massachusetts in 1869 by an amateur entomologist. Since then, spongy moths have defoliated millions of acres of trees in forests and urban areas in at least 20 states and the Washington D.C.…
The forest tent caterpillar is an important leaf-eating (defoliating) caterpillar in Wisconsin. Some people call forest tent caterpillars "army worms" because as they travel across the ground they look like marching soldiers.
Distribution
Forest…
Emerald ash borer (Agrilus planipennis) is an invasive, wood-boring beetle that kills ash trees (Fraxinus spp.) by eating the tissues under the bark. Native to northeastern Asia, emerald ash borer (EAB) was first detected in the United States in…
Beech bark disease is a major threat to American beech (Fagus grandifolia) in eastern North America. The disease is the result of an interaction between an insect (a scale) and a fungus (Neonectria) and it only happens when both are present.
Bark and ambrosia beetles (family Curculionidae, subfamily Scolytinae) are a diverse group of wood-boring beetles found in every forest type across the world. The United States and Canada are home to approximately 600 species of bark and ambrosia…
Learn here how to identify Asian longhorned beetle, where it is and how to help keep it from moving to new places. This pest is a serious threat to Wisconsin forests because it can attack many different tree species, even when the trees are…
The Wisconsin DNR maintains the locations of all stands confirmed with HRD. If you suspect HRD in your stand, please contact forest health staff for confirmation and consultation.
Heterobasidion root disease (HRD), formerly known as annosum root…
Hemlock woolly adelgid (Adelges tsugae) is a tree-killing insect that was accidentally introduced to eastern North America. It can become a threat to Wisconsin’s eastern hemlocks if it arrives here. Learn where this pest is now, what it looks like…
Wildfires pose a serious threat to public safety, property and our natural resources. Over 98% of all wildfires in Wisconsin are caused by people. Knowing the common fire causes, understanding the conditions under which fires can start and spread,…