August 29, 2017 12:17 Updated Follow If you have a tree that is showing signs of distress, insect damage or disease, your best sources of information are DNR's Division of Entomology (http://www.in.gov/dnr/entomolo/) and Purdue University's Diagnostic Lab (http://www.ppdl.purdue.edu/ppdl/). Related articles Where can I get more information about emerald ash borer (EAB)? What are the Duties of an Indiana Conservation Officer? How can I find an arborist? What native plants can I use for landscaping and where can I buy them? Can I carry a handgun while visiting an Indiana State Park?