Zach Wirtz leads the Chicago Region Trees Initiative (CRTI), The Morton Arboretum’s flagship urban and community forestry program, working to improve the health, diversity, and equitable distribution of trees in the Chicago region and throughout Illinois.
CRTI has collaborated with more than 500 partners across public, private, and nonprofit sectors to inspire tree stewards and build municipal capacity and support for trees to improve climate resilience.
With a solid background in nonprofit tree planting and urban forestry, Wirtz has honed his expertise through experience in both Texas and Illinois. He holds a bachelor of science degree in urban forestry from the University of Wisconsin-Stevens Point and a master of science degree in forestry from The University of British Columbia. He earned Arborist Certification through the International Society of Arboriculture (ISA) and ISA Tree Risk Assessment Qualification.
At CRTI, Wirtz continues to work toward nurturing green spaces and fostering sustainable urban environments with a collaborative approach.
His research interests include urban forest governance, volunteerism, and mitigating urban heat issues with trees.
Accomplishments
Wirtz has authored and co-authored peer-reviewed journal articles on urban forest governance, volunteerism in urban forestry, and urban afforestation. He presented his work at various local, national, and international conferences.
Since 2024, Wirtz has directed the Chicago Region Trees Initiative (CRTI) at The Morton Arboretum. Under his leadership, the program earned the 2025 APGA Program Excellence Award and the 2025 ASLA Olmsted Medal. Previously, as CRTI’s community manager, he oversaw more than 85 statewide community grants and spearheaded the creation of tree protection ordinance tools endorsed by the Illinois Department of Natural Resources. Notably, he led the transformation of an underutilized parking lot into the Mary Schmidt Community Sanctuary in Alsip, IL—a project honored by the Metropolitan Water Reclamation District and Friends of the Chicago River.
During his tenure at the Texas Trees Foundation, Wirtz co-led a team that developed the first Urban Forest Master Plan for the City of Dallas, TX.
Affiliations
Member, International Society of Arboriculture—Certified Arborist #PN-8591A, Tree Risk Assessment Qualification
Member, Illinois Arborist Association
Member, Illinois Forest Development Council, Urban and Community Forestry Committee
Member, American Public Garden Association
Member, Urban and Community Forestry Society
