You are here

Investigating new threats from emerging invasive plants

Date: October 05, 2015


Forest Service researchers investigating factors that contribute to the expansion of a recently introduced plant species into a native prairie.
Forest Service researchers investigating factors that contribute to the expansion of a recently introduced plant species into a native prairie.
Our national grasslands represent large tracts of native prairie and pose distinctive challenges to studying and managing invasive plants. Newly introduced species can quickly spread unimpeded across large areas of these uninterrupted landscapes, making early detection and rapid response critical components of invasive plant research and management.

Few studies focus specifically on recently introduced exotic plants in the early stages of establishment. Documenting patterns of invasion before species becomes widespread and identifying traits that may contribute to the success of recent invaders can increase our knowledge of factors influencing invasibility.

Key Findings

Forest Service scientists and partners developed an aggressive approach to investigate the biological and habitat characteristics of sickleweed (Falcaria vulgaris), a rapidly expanding invasive plant newly introduced into the grasslands of the Northern Great Plains and Upper Midwest. The research combines three approaches:

  • Analysis of herbarium records of sickleweed to reconstruct the introduction history and potential pathways of spread.
  • Detailed field surveys to describe the pattern of abundance and distribution of sickleweed and identify the factors that can predict the susceptibility of local and regional grasslands to invasion.
  • Cutting edge laboratory research on population genetics and seed germination and establishment characteristics of sickleweed.

Genetic analyses have identified the number and location of potential sites of introductions, and seed germination trials described the establishment and spread potential of the species. Collectively, these studies help managers develop a range of management alternatives that reduce establishment of new populations and limit expansion of existing populations. The researchers' approach also provides a template for future evaluations of newly introduced species before they become potential invaders.

Featured Publications

Piya, Sarbottam ; Nepal, Madhav P. ; Butler, Jack L. ; Larson, Gary E. ; Neupane, Achal , 2014
Butler, Jack L. ; Wacker, Stefanie D. , 2013
Piya, Sarbottam ; Nepal, Madhav P. ; Neupane, Achal ; Larson, Gary E. ; Butler, Jack L. , 2012

Principal Investigators: 
Forest Service Partners: 
Stefanie D. Wacker, Rocky Mountain Research Station
Nebraska National Forest
Buffalo Gap National Grassland
Fort Pierre National Grassland
External Partners: 
Sarbottam Piya, South Dakota State University
Madhav P. Nepal, South Dakota State University
Gary E. Larson, South Dakota State University
Achal Neupane, South Dakota State University