By Olivia Anderson and Jill Silver

Scotch Broom: A Yellow Menace on the Move

As summer arrives on the Olympic Peninsula, roadsides and meadows light up with bright yellow Scotch broom. Though striking, this invasive plant poses serious environmental, economic, and health risks. For allergy sufferers, its pollen is a seasonal irritant—but beneath the golden blooms lies a bigger problem.

A Spreading Threat

Scotch broom (Cytisus scoparius), native to the British Isles and North Africa, forms dense thickets that outcompete native vegetation and disrupt forest succession. It invades pastures, reduces forage quality for livestock, and crowds out crops. Its aggressive growth threatens forests, rivers, wildlife, and communities.

A Growing Fire Risk

Scotch broom significantly increases wildfire danger. Its woody stems, oily foliage, and buildup of dry plant matter create dense fuel loads. In 2023, wildfires burned over 174,000 acres in Washington, including 44,000 acres of forest. Though large fires are still less common on the west side, when they occur, they damage salmon habitat by warming streams, increasing sediment, and removing vital shade.

Public Health and Economic Costs

Wildfire smoke poses health risks to children, the elderly, and people with respiratory conditions. And the economic cost is steep—over $142 million annually in Washington. The Clallam County Noxious Weed Control Board recently secured $43,000 for Scotch broom control and preparation for upcoming timber harvests in the Olympic National Forest. They continue to emphasize the importance of managing infested areas to protect both ecology and economy.

What You Can Do

Each Scotch broom plant can produce up to 10,000 seeds, which remain viable in the soil for up to 80 years. By removing even one plant, you help stop its spread.

Start at the edges: Target scattered plants first and work toward dense infestations. This allows native plants to re-establish.

Time it right: Remove broom before it flowers and sets seed, usually May–June. Hand-pull small plants in moist soil, but monitor for regrowth.

Use the right tools: For larger shrubs, use a Weed Wrench™, available through the Clallam County Weed Board (360-417-2279) or 10,000 Years Institute in Forks (360-301-4306).

Cutting and treating: Mature plants can be cut in the dry summer months, when regrowth is slower. However, cutting alone often isn’t enough—cut stumps may resprout unless treated with herbicide. 10KYI offers guidance and resources.

Proper disposal: If pulled before seed production, broom can be left on-site to decompose. If seeds are present, bag and take to a transfer station or burn in permitted areas with a DNR burn permit.

Why It Matters

Clearing Scotch broom allows native trees like red alder, Sitka spruce, and Douglas fir to return, improving soil health, stabilizing stream banks, and restoring wildlife habitat. It also benefits pollinators, birds, and salmon—key parts of our local food web.

Removing just one plant is a meaningful act of restoration. Together, we can reduce wildfire risk, protect our forests and rivers, and reclaim native landscapes.

Need help?

Contact the Clallam County Noxious Weed Control Board or 10,000 Years Institute for tools, training, or advice.