Our Team
Zac Freedman (Principal Investigator)
Zac is interested in the ecology and environmental significance of microorganisms in a changing world. He completed his postdoctoral training at the University of Michigan with Dr. Don Zak and his PhD at Rutgers University with Dr. Tamar Barkay. Zac is a native of Evanston, Illinois and enjoys long bike rides, discovering new music, and all things hockey. Before embarking on a career in science, Zac was a camp counselor, a hot dog vendor at Wrigley Field in Chicago and a security guard at the Gorge Amphitheater in Washington State.
Zac’s CV
Emily Kauffman (Research Specialist)
Emily joined the Freedman Lab in August of 2026. As Research Specialist, she oversees daily lab operations and assists other lab members with various analytical needs. In her free time, she enjoys writing fiction and spending time with her cats.
Emily also serves as the Research Specialist for the Whitman Lab.
Gwen Pipes (PhD Student)
Gwen is a PhD student in the Freedman Lab and joined in 2022. She earned a B.S. in Environmental Science and an M.S. in Natural Resources from Cornell University. Gwen is interested in studying restoration in anthropogenically degraded landscapes and its impact on soil carbon storage. In her free time, she enjoys spending time with her cat, Atlas, doing art, and running.
Soni Ghimire (PhD Student)
Soni joined the Freedman lab in June 2023. She earned a B.S. in Agriculture from Agriculture and Forestry University, Nepal in 2019 and an M.S. from Virginia Tech in 2023. She is interested in Soil Science, Remote Sensing, and Data Analytics. Her previous work focused on estimating the contributions of soil and cover crop N mineralization for corn. Soni’s current work integrates the use of MIR spectroscopy and inexpensive soil sensing technologies to understand the crucial microbial processes, ultimately facilitating the improvement of next-generation biogeochemical models. She enjoys cooking, reading books, watching series, and spending time with her family during her leisure time.
Erica Shoenberger (PhD Student)
Erica is a PhD student in the Freedman and Picasso labs. She is conducting on-farm research in WI with the dual-purpose, perennial grain and forage, crop Kernza intermediate wheatgrass. She is exploring how transitioning land from annual to perennial grain cropping systems impacts soil health, microbial communities, and carbon dynamics. She loves camping, skiing, hanging out with her niece and nephew, growing an abundance of vegetables, and playing the guitar.
Erica’s CV
Hannia Ramírez (MS Student)
Hannia is an M.S. student in Agroecology and an AAUW and Fulbright Scholar. She joined the Freedman Lab in 2025 after earning a B.S. in Biotechnology from Tecnológico de Monterrey. Her research focuses on applied plant-microbe interactions to improve the resilience, performance, and sustainability of edible crops. Hannia is excited to explore her identity as a scientist and aims to integrate sociological and participatory research approaches into her work.
Andrew Molodchenko (MS Student)
Andrew joined Soils department as a master’s student in 2026 to study the effects of fungicides on soil microbiome and plant health with Dr. Freedman and Dr. Popova. Prior to that, Andrew was studying biology at Moscow State University and Biochemistry at UW. He likes exploring new parts of Wisconsin. Most recently, he plans to backpack the Ice Age trail.
Kate Clausen (Undergraduate Research Assistant)
Kate is a second year student studying Environmental Science at UW–Madison. She is intrigued by the interconnectedness of the environment, and how climate change affects its systems. She is also passionate about environmental policy and law making. In her free time she enjoys reading, spending time outside, and baking.
Lab Alumni
Postdoctoral Fellows
Dr. Grace Cagle (2022-2025)
Project: Using successional dynamics, biogeography, and experimental communities to examine mechanisms of plant‐microbiome functional interactions
Visiting Scholars
Dr. Erdal Yardim (2025-2026); Professor, Plant Protection Department. Siirt University (Türkiye).
Graduate Students
Brooke Propson (PhD, 2026)
Dissertation Title: From genes to ecosystems: Microbial and molecular drivers of soil carbon storage under changing nitrogen regimes
Brooke’s website
Tanner Judd (PhD, 2025)
Dissertation Title: Investigating Carbon and Nitrogen Cycling Across Agricultural Landscapes Through Probing of Microbial Mechanisms
Clare Tallamy (MS, 2025)
Thesis Title: Exploring Dynamics of Rhizosphere Microbiome Assembly in Organic Carrots (Daucus carota subspecies.)
Hannah Anderson (MS, 2023)
Thesis Title: Root exudation and rhizosphere microbial recruitment are influenced by novel cultivar development in organic carrot production.
Salvador Grover (MS, 2023)
Thesis Title: Early production of switchgrass (Panicum virgatum L.) and willow (Salix spp.) indicates carbon accumulation potential in Appalachian reclaimed mine and agricultural soil
Greg Martin (PhD, 2022)
Dissertation Title: Anthropogenic disturbance regimes impact the microbial and chemical composition of soils and sediments across ecosystem
Jen Kane (MS, 2019; PhD, 2022)
MS Thesis Title: Soil microbial succession following surface mining is governed primarily by deterministic factors
PhD Dissertation Title: Cross-kingdom interactions shape soil biogeochemistry in natural and agricultural ecosystems
Brianna Mayfield (MS, 2019)
Thesis Title: Mine reclamation using biofuel crops: Insights into the microbial ecology of the switchgrass (Panicum virgatum) microbiome.
Jordan Koos (MS, 2018)
Thesis Title: Prescribed defoliation strategies influence soil carbon storage and nitrous oxide emission potential in West Virginia pastures
Undergraduate Students
Linnea Pelto (Undergraduate Research Assistant, 2024-2026)
Eden Milan (Undergraduate Research Assistant, 2024-2025)
Ethan Krull (Undergraduate Research Assistant, 2023-2025)
Emily Sautebin (Undergraduate Research Assistant, 2022-2024)
Mar Gut (Undergraduate Research Assistant, 2022-2023)
Jeremy Fleck (Undergraduate Research Assistant, 2021-2023)
Amalia Petropoulos (Undergraduate Research Assistant, 2021-2022)
Alessia Fucentese (Undergraduate Research Assistant, 2021-2023)
Anella Cousin (Undergraduate Research Assistant, 2020-2022)
Annalisa Stevenson (Independent Study, 2020)