Flora of Fort Laramie National Historic Site

Heidel, Bonnie

Fort Laramie National Historic Site (FOLA) is a landmark of western history. It lies at the confluence of two major rivers, the North Platte and the Laramie Rivers, which were Rocky Mountain travel corridors and gateways to natural resources for traders, military personnel, settlers, and Native Americans alike. This report addresses the culmination of work documenting the FOLA flora, and the lessons learned. Baseline floristic inventory at FOLA was identified as a priority by the NPS under the Inventory and Monitoring initiative. The first step was to compile and interpret existing floristic information from earlier vascular plant collections made in FOLA and in the county (Fertig 2001). From these data, a total of 178 plant species were reported. This represented 26.7% of the Goshen County flora known at that time. Systematic floristic inventory conducted at FOLA (2003 – 2004) more than doubled the documented flora (Heidel 2004). Since that time, the flora has been expanded by short visits in favorable years and in under-sampled periods and with online data searches. It has also been cross-checked with specimen data and redefined in sorting between those specimen records that are from the Historic Site versus those only on nearby BLM tracts. There is a current tally of 355 vascular plant species in FOLA in addition to 57 species only known from nearby BLM tracts (Marriott 2022). The results are represented for ease of access in NPSpecies. This report chronicles the process for robust floristic documentation as it reflects remnant high plains vegetation, a high proportion of nonnative species (33.7%), two species additions to the Wyoming flora (a native and a nonnative species), and a critical resource base for reference in any restoration planting or cultural plants developments. The baseline floristic information provides a management reference, biogeographic reference, and a natural history reference befitting the rich human history.