Botanical survey of Lupine Meadows
Lupine Meadows is a 58-acre property owned by the Greenbelt Land Trust (GLT). The GLT aims to protect, restore and manage rare native habitats and rare species to provide low-impact
Lupine Meadows is a 58-acre property owned by the Greenbelt Land Trust (GLT). The GLT aims to protect, restore and manage rare native habitats and rare species to provide low-impact education, recreation and ecological research. In addition, the GLT desires to use Lupine Meadows in partnership with public agencies and private landowners and organizations to promote restoration and management of native habitats in the Newton Creek area.
The Lupine Meadows Management Plan places the highest priority on restoration of this, area with emphasis on Fender’s blue butterfly (Icaricia icarioides fenderi) and Kincaid’s lupine (Lupinus oreganus also known as L. sulphureus ssp. kincaidii).
In spring 2011, we conducted vegetation surveys at Lupine Meadows to document the availability of host and nectar plants for Fender’s blue butterfly and the distribution of exotic plant species. Specifically, the goals of this project are to:
- Establish a permanent monitoring plot and protocol in the area of Lupine Meadows occupied by Kincaid’s lupine and nectar species for Fender’s blue butterfly.
- Measure the amount of Kincaid’s lupine at Lupine Meadows.
- Describe the diversity, amount, and distribution of nectar species for Fender’s blue butterfly.
- Survey and map invasive species at Lupine Meadows, with particular attention to species that (a) have the potential to become problematic, and/or (b) could be relatively easily managed. Obvious invasive species such as Himalayan blackberry and Scotch broom were not mapped.
In 2011, cover of Kincaid’s lupine at Lupine Meadows was 185 m2. There is substantial unoccupied habitat at the site into which the species could spread. The monitoring protocol used in 2011 should be used to track changes in population size and the effects of management treatments through time.
We identified thirteen species of nectar plants for Fender’s blue butterfly at Lupine Meadows. Although most of these species occurred in trace amounts, there was significant cover of three species (oxeye daisy, Virginia strawberry, and slender cinquefoil); in some areas, these species occupied greater than 25% cover. Nectar species that flower throughout the flight-time of Fender’s blue butterfly were present. Several of the nectar sources were exotic species; control of these species should be paired with increasing the abundance of nectar species with similar flowering phenologies (e.g. with targeted management and/or seeding).
Although there were many more exotic plant species found at the site (e.g. vetch species, [Vicia spp.] and hairy cat’s ear [Hypochaeris radicata]), our surveys focused on documenting those species presenting the greatest threat and/or occurring in patches that could be controlled with a concentrated effort. In general, we found a greater abundance of invasive species in the southern portion of the site. Our recommendations for prioritizing weed control are as follows:
- Remove shrubs near nectar species and Kincaid’s lupine. The shrubs not only compete with Kincaid’s lupine, but may also decrease the apparency of larval host and nectar species of Fender’s blue butterfly (Severns 2008).
- Remove false-brome, meadow knapweed, and reed canarygrass as these species have the highest potential of rapidly spreading through the site.
- False-brome should either be pulled or culms clipped and removed before any brush hogging, mowing, or other activities that could spread seeds.
