Jill Koski is president and CEO at The Morton Arboretum, an internationally recognized tree-focused botanical garden 25 miles west of Chicago in Lisle, Illinois. In her role, she oversees the organization’s mission is to plant and protect trees for a greener, healthier, and more beautiful world where people and trees thrive together. She is the Arboretum’s fourth leader in its 100-year history and the first woman in that position.

Jill came to The Morton Arboretum from Holden Forests and Gardens in Ohio where she was president and CEO from 2017 to 2022. Prior to that, she was vice president of development at The Morton Arboretum for 10 years. Her previous experience includes leadership roles in science-focused environmental nonprofits, namely the John G. Shedd Aquarium and the Peggy Notebaert Nature Museum in Chicago. Jill holds a Bachelor of Arts degree in political science from the University of Wisconsin–Madison.

The Morton Arboretum encompasses 1,700 acres of tree and plant collections, with specialty gardens amid natural landscapes. The organization works to create an impact on the quality of life. It conducts scientific research to improve the health and care of trees, which provide essential benefits for the environment, people, and communities. In addition, the Arboretum provides nature-based education programs to build appreciation for trees. As an outdoor museum and public garden, it is a cultural destination showcasing trees and engaging the public. The Morton Arboretum welcomes more than one million visitors each year and employs 500 people who are supported by 1,000 volunteers.