The Great Scotch Broom Census: help state locate, eliminate the invasive plant species

There’s a little-known council in our state – the Washington Invasive Species Council (WISC) – that provides policy direction, planning and coordination to help prevent, detect and eradicate invasive species. It is also serves as a forum for invasive species education and communication.

In May the council helped launch the The Great Scotch Broom Census. Did that leave you saying ‘huh’? Us, too, at first.

But as someone highly allergic to that yellow flowering plant often spotted beside Snoqualmie Valley roadways, I was intrigued.

Scotch broom is found in 75% of counties across Washington, but its specific locations and patch sizes aren’t well documented. Hence, the scotch broom statewide census.

Why do state officials want to know its specific location? Simply put, the yellow-flowering (usually in May) plant is a problem.

According to WISC, scotch broom crowds out beneficial native species and clogs healthy habitats. It can form dense, impenetrable stands that are a problem for grazing, farming and recreating and it creates fire hazards.

Dense stands may also prevent or slow forest regeneration and harm sensitive areas near streams and wetlands. And if that wasn’t enough, scotch broom also produces toxic compounds, which in large amounts may poison grazing animals.

Enter the Washington State Great Scotch Broom Census.

“We need everyone’s help to size up the problem,” said Justin Bush, executive coordinator of the Washington Invasive Species Council. “Without baseline information about the location and population size, we don’t have enough details to determine solutions. The information from the census will help us set short- and long-term action plans.”

Residents are asked to report scotch broom sightings, which should include a photograph of the plant that shows enough detail that the plant can be verified by an expert. A description of the size of the patch is also helpful, such as whether the patch is the size of a motorcycle, a car, a school bus or multiple school buses.

Info can transmitted to the council by using the Washington Invasive’s mobile app found at Photographs also can be shared with the council on FacebookInstagram and Twitter by using the hashtags #TheGreatScotchBroomCensus and #ScotchBroom2020Census.

While widespread and not likely to be fully eliminated from the entire state, action is being taken to remove Scotch broom from parks, roadsides, forests, riverbanks and other at-risk landscapes. The information from the Scotch broom census will help invasive species managers better understand the needs of landowners and managers.

“We don’t have the resources at a state or local level to remove every Scotch broom,” said Greg Haubrich, pest program manager with the Washington State Department of Agriculture. “But organizations like your local noxious weed control board can provide education and technical assistance so that you can efficiently and effectively manage Scotch broom on your property. In some instances, there also could be cost-share funding available from your local conservation district to remove your Scotch broom.”

Washington is currently in a friendly competition with Oregon to see which state can collect the most scotch broom reports. As of May 23rd, Washington is wining.

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  • Scotch Broom has been recognized in Oregon for years as an invasive species. Plant outlets can’t sell the stuff. Even though I’m highly fond of the flowers this time of year, they will crowd out grasses and other vegetation that elk and deer count on in open meadows.

    Round-up and perhaps other weed killers work well on the plant and the best time to spray (carefully) is before flowering as they are prodigious seed spreaders. The leaves are quite small so wet down the branches on the main stem.

    There are not a lot of plants or animals that I have no use for but I actively discourage poison oak/ivy, broom and skunks.

  • Ship them to the east coast for landscape use, they don’t seem to be invasive at all over here

  • Glad to see the state finally taking action on this. It would be great to see a similar campaign taken to combat invasive Himalayan Blackberry.

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