Staff Directory


Jennifert Antonides

Post-doctoral Research Associate

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Lorenzo Cotrozzi

Post-doctoral Research Associate

Dr. Cotrozzi’s research interests are plant responses to simultaneous biotic and abiotic stress and vegetation spectroscopy.

Lenny D. Farlee

Lenny D. Farlee

Sustaining Hardwood Extension Specialist

Lenny is an extension forester with the HTIRC. He provides programs and publications in a variety of media directed toward improving the regeneration and sustainable management of high quality hardwood trees and forests in the Central Hardwood Region. Learn More

Janis L. Gosewehr

Janis L. Gosewehr

Administrative Assistant

Janis provides administrative support to the HTIRC. Learn More

Nathanial C. Hilliard

Nathanial (Nathan) C. Hilliard

Laboratory Manager

Nathan is the lab manager for Forest Ecology, Soils and Silviculture Lab, the Molecular Tree Physiology Lab and the Wright Research Center Lab. Learn More

Elizabeth “Liz” A. Jackson

Elizabeth “Liz” A. Jackson

Manager Walnut Council/IFWOA and Engagement Specialist for HTIRC

Liz is the Engagement Specialist for HTIRC, Executive Director of the Indiana Forestry & Woodland Owners Association, and the Executive Director of the National Walnut Council. Learn More

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Caleb Kell

Research Forestry Technician

Jim McKenna posing with trees

James “Jim” R. McKenna

USDA Forest Service, Operational Tree Breeder or

Jim works as part of a team of scientists, professors, and students in the Department of Forestry and Natural Resources, along with other researchers at Purdue, the U.S. Forest Service. Learn More

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Patrick O’Neil

Genomics Laboratory Manager


Anna Sugiyama

Post-doctoral Research Associate

Anna is studying local adaptation and phenotypic plasticity for restoration of a native tree species in Hawaii.

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Lydia Utley

Data Analyst

Lydia works on data analysis for the Center. Learn More


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Holly Wantuch

Post-doctoral Research Associate

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James “Jim” C. Warren

USDA Forest Service, Biological Scientist/Operational Tree Breeder or

Prior to coming to the HTIRC, Jim assisted in running the daily operations of the Minnesota Tree Improvement Cooperative at the University of Minnesota’s Cloquet Forestry Center for 17 years.  His primary duties entailed designing, implementing, and measuring field trials, assisting with orchard management, conducting tree breeding and grafting, and collecting data. Learn More