Oregon: Noxious Weed Control Program Takes to the Skies

To the casual observer, it probably looked like someone in a helicopter who had finished their 16 ounce soft drink and simply discarded the paper cup by throwing it out the window. But what appeared to be aeronautical littering was actually the release of tiny beneficial insects with an appetite for the invasive noxious weed Scotch broom.

The Oregon Department of Agriculture teamed up with the Bonneville Power Administration late this spring to reunite Scotch broom with a natural enemy? Brichidius villosus, otherwise known as a seed beetle. It is estimated that Scotch broom costs Oregon $47 million annually in lost timber production and by its impact on other natural resources.

For BPA, controlling the broom keeps the rite-of-way located under transmission lines clean and clear. For ODA, the beetle release is another example of biological control of an invasive and unwanted plant species. More than 30 bio-degradable soft drink containers each containing 100 of the beetles were tossed from a BPA helicopter over targeted patches of the yellow-flowered weed. Holes punched in the bottom of the cups allow the beetles to eventually crawl out and onto the broom. It's a low tech application of a highly specific tool that only impacts the invasive plant.

While it may be too late to eradicate Scotch broom from Oregon, biocontrol is helping to manage the problem and slow its spread. ODA is a leader in using biological control agents on targeted weed species. The aerial assault on Scotch broom is just one of the latest in a long line of projects that show promise.