Got Nature? Blog

Starting in 2019, sassafras trees began wilting and dying in southern Indiana. It was originally thought that laurel wilt, a deadly disease in the southeastern U.S., had made its way to Indiana. However, neither the fungus responsible for causing laurel wilt nor its beetle vector were recovered from wilting trees at the time. A potentially novel fungus was recovered, as well as two invasive ambrosia beetle species. Invasive insects, particularly bark and ambrosia beetles are well-known carriers of devastating disease-causing fungi. Dutch elm disease is one of the most famous examples of a beetle-transmitted disease.

Sassafras trees are an important understory tree that aids in nutrient cycling and are important food sources for deer and rabbit populations in the winter months. They are also important to native butterfly populations like the Swallowtail butterfly, that uses sassafras as a host. At this time, we do not know what is killing our native sassafras trees or the range of impacted trees. This is a problem because if we do not know what is causing wilt or where trees are wilting, then we cannot work to identify ways to protect our native sassafras trees.

We need more help in identifying locations of wilting sassafras trees. We anticipate trees to start wilting towards the end of the summer, from late July through September. If you see any wilting or dying sassafras trees, please email sassafras.wilt@gmail.com to report it. You can also use the QR code on the bottom of the attached handout.

To learn more see the attached Sassafras Wilt Report Flyer.

Resources:
Report Invasive Species, Purdue Invasive Species
ID That Tree: Sassafras
ID That Tree: Sassafras Spring Bloom Edition
Morton Arboretum: Sassafras
Sassafras, Purdue Fort Wayne Native Trees of Indiana River Walk
ID That Tree Spring Bloom Editions, Got Nature Blog
Hardwood Lumber and Veneer Series: Sassafras, The Education Store
Purdue Arboretum Explorer
The Woody Plant Seed Manual, U.S. Forest Service
Native Trees of the Midwest, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Olivia Bigham, Graduate Student
Purdue Forestry and Natural Resources & Hardwood Tree Improvement & Regeneration Center (HTIRC)

Matt Ginzel, Associate Professor
Purdue Forestry and Natural Resources & Department of Entomology