October 17, 2024
Here at the San Juan County Noxious Weed Program, our charge is to help manage invasive vegetation on our islands. In that endeavor, we roam the roads and parcels constantly surveying changes in plant cover.
Early last Spring, before deciduous plants flooded the voids between bare branches with fresh green leaves, Scotch broom seemed to be everywhere I looked. The distinctive color and form of broom plants made them easy targets for removal. As plants across the islands burst into golden flowers, I frantically stopped along the roadsides to snuff them out before they could ripen a new seed crop (Broom seed can lay dormant in the soil for decades!). Soon I started seeing less broom, even in the places where I could swear (pleasantly) that I'd seen plants just a few weeks before. Was I that good? Had I really gotten all the broom in that area? As it turns out: I'm not that good. Once again the leaves are disappearing, revealing those darn broom plants like a lame magic trick, and right where I'd suspected they were!
That's how it is with invasive plants. They are incredibly tough to eradicate. But that doesn't mean we shouldn't spend some time keeping them corralled. One need only look to the unmanaged roadsides and logged areas of the mainland to see the potential of broom to aggressively transform habitat and agricultural land into a monoculture of its own.
We're entering an opportunistic season when the increased visibility of broom coincides with us generally having more time and capacity to attend to it. The lawn doesn't need to be cut; the bustle of summer vacations and visitors is a memory. Now's the time to tick away on noxious shrubs like Scotch broom and spurge laurel. As with most weeds, the best management strategy is to focus on the margins of an infestation first, then work toward the dense areas. I recommend hand-pulling small plants out by the root. If you're yanking up wads of soil with your broom, it's a sign the plants are too large for pulling. Remember: broom seed lives for soil disturbance. Instead, sharpen up your hand pruners or loppers and nip the plants off as low to the ground as possible. Be sure to follow up the cut with a quick dab of the right herbicide, or the beheaded broom will resurface in an angry octopus of arms that will leave future you (or unfortunate helper) groaning with disappointment. Octopus plants are a bear to remove! For the same reason, PLEASE DO NOT MOW broom unless you have a plan to treat the patch with an appropriate herbicide. Mowing in any other way will just create more work in the long run.
For more pictures of Scotch broom and information on management techniques, check out the Washington State Noxious Weed Board page on broom.
Need more advice or assistance tackling your broom patch or other weeds? Get in touch! Noxiousweeds@sanjuancountywa.gov or 360-376-3499.