POSTER PRESENTER CO-AUTHORS: Holly M. Johnson, Sara G. Niemuth (UW-Madison); Tony Klingert (UW-Green Bay); Mary Ann Feist (Wisconsin State Herbarium) TITLE: Bridging the gap: Historical insights from 185 years of sphagnum moss collections in Wisconsin peatlands ABSTRACT: Peat mosses (Sphagnum) are foundational components of peatlands, shaping hydrology, nutrient cycling, and carbon storage while serving as sensitive indicators of wetland integrity. However, despite their ecological importance, Sphagnum mosses have been historically under-collected and understudied in Wisconsin. Much of our early knowledge comes from the work of Lellen S. Cheney, whose four decades of fieldwork from 1892 to 1932 established the foundation for our understanding of the state’s moss flora. Later collectors such as Frank Bowers and Rudy Koch contributed important surveys in the latter half of the 20th century, but a substantial gap in sustained Sphagnum collections persists, reflecting both the taxonomic challenges of the genus and a broader decline in bryological fieldwork. This poster presents a temporal and spatial analysis of Sphagnum collections from 1840 to 2025 across Wisconsin and neighboring states, revealing long-term trends and significant regional gaps in documentation. By visualizing these patterns, we highlight the need for renewed collecting and taxonomic study to update our understanding of regional Sphagnum diversity and distribution in a changing climate. Ongoing surveys through the Students and Water in Wisconsin’s Peatland Plant Communities project are helping to fill these gaps, providing contemporary data that support wetland monitoring, conservation, and restoration. Together, these efforts highlight the scientific value of natural history collections, community engagement, and the importance of continued, targeted study of these keystone peatland organisms. BIO: Brandon Corder is a PhD botanist and research technician at the Wisconsin State Herbarium specializing in Great Lakes orchids and peatland bryophytes.