UW News

September 22, 2006

UW Botanic Gardens site of first regional conference on invasive plants in PNW

“Invasive plants are degrading ecosystems, lowering land values and affecting everyone,” says Sarah Reichard, associate professor with the University of Washington Botanic Gardens and lead organizer of the conference. Two hundred people from around the country are expected to discuss how to manage plant invasions in the Pacific Northwest.

Tuesday and Wednesday, Sept. 19-20
Center for Urban Horticulture, UW Botanic Gardens
Directions: http://depts.washington.edu/urbhort/html/info/images/drivingdirectionsmappdf.pdf

 Media opportunities

  • Reichard will be available during the morning breaks, 10:10 to 10:30 each day.
  • Opening session, Tuesday, 9:10 to 10:10 a.m., features John Randall, Nature Conservancy’s Wildland Invasive Species Team leader, based at University of California
  • Other key speakers include Les Mehrhoff, one of the project managers of the Invasive Plant Atlas of New England project; Ann Bartuska, deputy chief for research and development for the USDA Forest Service and former executive director of the Nature Conservancy’s Invasive Species Initiative; and Doug Johnson, with the California Invasive Plant Council.

Conference schedule


  • UW Botanic Gardens, a part of the UW College of Forest Resources
  • Pacific Northwest Research Station, USDA Forest Service
  • Nature Conservancy
  • Center for Invasive Plant Management


  • The idea for the conference is to bring people together and develop partnerships to be more effective in addressing this problem, Reichard says. The conference is bringing people together from local, state agencies and non-profits, from Alaska to California.
  • This is an increasingly complex issue in the Pacific NW, and is getting worse because of increased travel and disturbance to land, she says.
  • Invasive plants are the second leading cause of endangerment of native plants according to work published by David Wilcove in 1998.
  • Invading non-indigenous species in the United States cause major environmental damages and losses adding up to more than $138 billion per year, according to David Pimentel of Cornell University.
  • “Alien Invasion,” Columns magazine, 2003, http://www.washington.edu/alumni/columns/sept03/invasion01.html  

Examples of problem plants in PNW:

  • English and Atlantic ivy
  • Knotweed
  • Leafy spurge, a problem in rangeland, which can reduce the value of land from hundreds of dollars per acre to pennies an acre.
  • Scotch broom, which transforms the ecosystem by increasing the nitrogen levels in grasslands. This is a long-term problem because you can’t just pull it out and the ecosystem will restore itself; the soil chemistry is altered.
  • “The 10 worst invaders in Pacific Northwest,” Columns magazine, 2003, http://www.washington.edu/alumni/columns/sept03/invasion_side.html  

For more information:
Reichard, (206) 616-5020, reichard@u.washington.edu