Many insects are not actually the cause of tree mortality but simply “opportunists” and infest decaying wood. Spraying the remaining trees depends on the insects and their propensity for infesting live trees.

Cut wood, especially if infested, should never be moved out of the county to minimize the spread of harmful pests. See more at www.dontmovefirewood.org.

Resources
Walnut Anthracnose, Walnut Notes, U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station
Indiana Walnut Council, Industry Representatives include 45 states and 3 foreign countries
Diseases in Hardwood Tree Plantings, The Education Store, Purdue Extension resource center
Study: Fungus Behind Deadly Disease in Walnut Trees Mutates Easily, Complicating Control, Purdue Agriculture News
Thousand Cankers Disease
Walnut Twig Beetle and Thousand Cankers Disease of Black Walnut, Purdue Plant and Pest Diagnostic Laboratory
Indiana Walnut Council
Diseases in Hardwood Tree Plantings, The Education Store, Purdue Extension resource center
Why are my walnut trees dropping their leaves?, Purdue Extension – Forestry & Natural Resources (FNR) Got Nature? Blog
Invasive Species Walnut Twig Beetle Detected in Indiana, Purdue Extension – FNR Got Nature? Blog
Intro to Trees of Indiana: Black Walnut, Purdue Extension – FNR Got Nature? Blog
Resources and Assistance Available for Planting Hardwood Seedlings, The Education Store
Certified Arborist (International Society of Arboriculture)
Pests of Concern, Walnut Twig Beetle, Indiana Department of Natural Resources
Invasive Species Walnut Twig Beetle Detected in Indiana, Purdue Extension – Forestry & Natural Resources (FNR) Got Nature? Blog

Purdue Extension – Forestry & Natural Resources (FNR)