BRCA vegetation crew exotic plant control activities - 2002 season

Welch, Joanna; Kohlmetz, Dale

This report summarizes the 2002 season of the Bryce Canyon National Park vegetation crew exotic plant control activities. In the 2002 field season, 102 sites were visited and/or treated, and 33 new sites were documented and treated. Approximately 40,000 individual non-native plants were controlled. The report outlines activities at individual sites throughout the park and describes management techniques and herbicides/equipment used. An attached addendum to the report provides corrections to this report.... Introduction: Bryce Canyon National Park has a relatively short history of non-native vegetation control. There has been very little information collected concerning non-native species prior to 1979. Surveys were conducted in park drainages for Tamarix ramosissima and Elaeagnus angusitifolia (Russian Olive), in 1979 (first mention of T. ramosissima), 1990, 1991, and 1992, these are both “noxious” plant species that require the use of an herbicide for successful control. Though surveys were conducted it was not until 1993 that the first formal exotic plant control program in the history of the park was implemented. Early in 1993, the Chief of Resource Management began preparations for an exotic plant control program and implemented the program that summer. The 1993 survey included a “comprehensive extermination program”. In 1994, a follow-up study was performed to determine the success of the 1993 program and to exterminate any surviving plants. The only non-native plant species that has documented control and eradication prior to 1993 is Cirsium vulgare (Bull Thistle). At that time the main population was at the Mixing Circle and Horse Corral area, this population seems to have been successfully eradicated, only to become a larger problem in other areas of the Park. C. vulgare has now become one of the main non-native species in the park with large populations along the main Park road and in Swamp Meadow.