WWETAC Projects

Project Title: Aspen decline rapid threat assessment

Status: Ongoing

Principal Investigator: William R. Jacobi, Colorado State University

E-mail Contact: William.Jacobi[at]ColoState.EDU

Summary: The declining health of trembling aspen (Populus tremuloides Michx) communities throughout the west is concerning the public, scientific communities, and land managers in both recent years and historically. Over the past decade, a noticeable loss of acreage has incited ground level aspen health plot establishment by scientists throughout the west, including Arizona, Colorado, Wyoming, Utah, Nevada, Idaho and Montana, with additional projects scheduled for the next two years. The recent onset of detailed, ground-level stand condition data in aspen ecosystems both highlights the urgency to define the status of aspen health and offers unique opportunities for collaboration and information sharing among states and research groups.

A Rapid Threat Assessment (RTA) defining the state of aspen health is needed, and will coordinate aspen health datasets throughout various regions in the western U.S. The RTA will attempt to qualitatively and quantitatively define and characterize the exposure of aspen to current threats, and determine the feasibility and scope and objectives of examining the current state of those threats.

Study Objectives:

  1. Describe the current state of aspen health (loss/gain of acreage, aspen decline/dieback, sudden aspen decline) throughout western North America using the presence of available aerial and ground aspen health surveys and recent literature
  2. Describe consequences of diminishing aspen stands on various ecosystem services and stakeholders throughout the west using available literature
  3. Solicit and combine aspen health datasets available to determine feasibility of data to expand upon regional explanations of aspen decline
  4. Develop and test two case studies: Use combined datasets from at least two geographic regions to determine feasibility of comparing and contrasting relationships between biotic damage agent incidence and severity, land use, site factors, and climate variables

Aspen health survey locations.
Figure 1. Location of aspen health survey plots compiled by CSU as of April 2010 (does not include Region 4 plot locations).

Project ID: FY09TS60