1a. Objectives (from AD-416)
Human impacts on the environment are altering species composition in many of the nation's national parks. One such impact is the increase in invasive plant species which are quickly over-running many of the native plant species. One such invasive species is Japanese stiltgrass (Microstegium vineum). The objective of the current research is to quantify human impacts, particularly nitrogen deposition, carbon dioxide and light on the ability of this species to grow and propagate.
1b. Approach (from AD-416)
Working with the National Park Service's Center for Urban Ecology, we will obtain local seed from stiltgrass populations and determine growth and see production utilizing a range of nitrogen deposition rates and carbon dioxide concentrations under glasshouse and growth chamber conditions. Data will be utilized in a multiple regression model in order to ascertain whether human induced changes in macroclimate near the D.C. area will contribute to the peniciousness of this invasive species.
3. Progress Report
Seed was obtained from three different locations, Eastern Shore, Catoctin National Park and Central Pennsylvania. A weed population by nitrogen by light interaction study to examine biomass and seed production was initiated in April. Harvest is planned for mid-July. In addition, two weather stations were installed at Catoctin National Park, one roadside, and one 50 meters in; both locations within an existing field of Stiltgrass. These stations include light, humidity, soil and air temperature, soil moisture, wind speed, and direction. A second replication of the experiment was planted in May and is currently underway. Meteorological and edaphic data are currently being collected and analyzed. Monthly collaborative meetings between ARS and the National Park Service are held at Catoctin National Park. In addition, annual meetings (since 2008) have been held at the National Park Service’s Center for Urban Ecology with ARS and NPS.