High Elevation Ephemeral Geophytes: Fire & Other Disturbances at Snowline
November 20, 2025
7:00 – 8:00 PM (Via Zoom)
by Hal Mackey
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Ephemeral geophytes at high elevations are only available for study for five to six weeks after snowmelt and therefore are rarely investigated. From 2009 to 2021, Hal Mackey and Rob Schlising collected life history data on the closely related Dicentra uniflora Kellogg and Dicentra pauciflora S. Watson (Papaveraceae) in the Cascade Range of northeastern Butte County, California, through field surveys and plantings. The field data were supplemented with CCH2 herbarium records from the late 1890’s to the mid-2020’s. These combined data provided a baseline to assess the effects of Dixie Fire in the summer of 2021, which burned to varying intensities in three of their study sites and multiple plots within each site. Post-fire surveys from 2022 through 2025 showed fire responses that ranged from slight to catastrophic, depending on the fire intensity. There were also unexpected post-fire consequences from other plants and animals. In addition to Dixie Fire impacts, another Dicentra study location near Butte Meadows was impacted by fire line construction during the Park Fire in the summer of 2024. These 16 years of data, both pre- and post-fire, have provided insights into recovery times and persistence after major forest fires.
Dicentra uniflora
Dicentra pauciflora
Hal Mackey received his PhD from the University of Tennessee and has worked on environmental projects for the past 54 years. As a professor teaching environmental sciences at the University of Pittsburg in Johnstown, he researched American chestnut regrowth in forests of western North Carolina and Pennsylvania. Earning a second degree in Public Health at the University of North Carolina at Chapel Hill, he became a senior environmental scientist with a federal government contractor at the Savannah River Site in SC, where he coordinated environmental assessments, and used satellite, multispectral and lidar data to map and evaluate wetlands on the 300-square-mile site. He was also instrumental in developing foraging ponds for the endangered American wood stork, and in mapping previously unknown nuclear waste sites from 1950s historical photographs for cleanup and closure. Since retiring and moving to Chico in 2008, he has worked with Rob Schlising to explore the natural history of two Northern California geophytes and their responses to snow patterns and climate change, work summarized in two publications in Madroῆo. When he’s not pursuing science, he enjoys working in his organic vegetable and fruit tree garden in his backyard and would be happy to give tours.