Invasive exotic plant monitoring at Golden Spike National Historical Park: 2018 field season
Washuta A and Perkins DW. 2019. Invasive exotic plant monitoring at Golden Spike National Historical Park: 2018 field season. Natural Resource Report. NPS/NCPN/NRR—2019/1938. National Park Service. Fort Collins, Colorado
Invasive exotic plant (IEP) species are one of the biggest threats to natural ecosystem integrity and biodiversity, and controlling them is a high priority for the National Park Service. The Northern Colorado Plateau Network (NCPN) selected the early detection of IEPs as one of 11 monitoring protocols to be implemented as part of its long-term monitoring program. This report represents work completed during the 2018 field season at Golden Spike National Historical Park (NHP). On July 2–4, 2018, we recorded a total of 17 IEP species during monitoring at Golden Spike NHP. Seven priority species were detected in 73 patches along 20 kilometers (12.4 miles) of 13 monitoring routes that covered all major roads, trails, and riparian areas. Three additional IEP species were recorded only in transects. The highest densities of plant patches were recorded along the Hydro 1 and Last Cut drainages and Retired Service and Facility roads. Scotch thistle (Onopordum acanthium) was the most prevalent priority species, representing 51% of all recorded patches. Field bindweed (Convolvulus arvensis), rush skeletonweed (Chondrilla juncea), and moth mullein (Verbascum blattaria) constituted most other patches. One patch of broad-leaf pepperwort (Lepidium latifolium) and one patch of Canada thistle (Cirsium arvense) were found in 2018; neither species had been found since 2014. A voucher specimen of broad-leaf pepperwort was collected. The number of IEP patches and total IEP patches per kilometer did not change greatly between 2016 (67/3.43) and 2018 (73/3.74). The total IEP patches per kilometer remained lower than in 2014 (4.96), but has increased since the earlier monitoring seasons of 2010 (2.33) and 2012 (0.36). This year, a metric called the patch management index (PMI) was added to our analy-sis. PMI combines the size and density of a patch to assess its scale. Almost all patches (96%) were classified as “very low” or “low” in PMI, suggesting that effective control or eradication is possible through local management actions. The network will return to Golden Spike NHP for a seventh year of monitoring in 2020.
- Type
- Published Report
- Authors
- Washuta, Amy; Perkins, Dustin
- Date of Issue
- 2019-06
- Publisher
- National Park Service
- Units
- GOSP , NCPN , NRSS
- Keywords
- Exotic Species, Exotic/Invasive Species - Plants, Invasive Species, Monitoring, NCPN Invasive Plants Monitoring, Plant Studies
- Subjects
- Ecological Framework: Biological Integrity | Invasive Species | Invasive/Exotic plants