Submitted to: Smithsonian Magazine
Publication Type: Popular Publication
Publication Acceptance Date: January 1, 2005
Publication Date: February 1, 2005
Citation: Smith, L. 2005. Letter to editor regarding "Wicked Weed of the West". Smithsonian Magazine. February 2005, p.16. Technical Abstract: As scientist working on control of invasive weeds, I was delighted to see your article, "Wicked Weed of the West". Invasive species are a continuously increasing threat to our environment and economy, and deserve more of our attention. Classical biological control has successfully reduced populations of many widespread invasive alien weeds. The research by Drs. Callaway, Vivanco, Pearson and their associates has raised interesting new perspectives, but unfortunately it has not yet revealed any new practical way to control these weeds. It is worth noting that the introduced insects are already successfully controlling diffuse knapweed (a close relative of spotted knapweed) in at least four U.S. states and Canada. Spotted knapweed is more difficult to control because it is a perennial, but it is now decreasing in the Bitterroot Valley of Montana. None of the introduced insects have attacked any nontarget plants. The indirect effect of insect larvae being eaten by field mice should vanish as the weed population decreases. Classical biological control remains the best available option to manage invasive alien weeds once they have become widespread.