Tolt MacDonald infestation stopped in its tracks by quick-acting King County Parks workers

Garlic mustard is a tricky noxious weed that usually escapes notice until it’s too late. This inconspicuous plant is often spread by hikers and animals unwittingly carrying the seeds along woodland trails, such as the one where it was discovered in Tolt MacDonald Park this August by King County Parks employees Chris Beckman and Keith Shanko. The plants were still small and most people would have overlooked them, but fortunately these Parks workers were both trained and observant, and may well have saved this park from being overrun with garlic mustard.

Garlic mustard infestation found at Tolt MacDonald Park by King County Parks workers in August 2016. Photo by Roy Brunskill.
Closeup of garlic mustard infestation at Tolt MacDonald Park. Photo by Roy Brunskill.

What happened after Chris and Keith found the garlic mustard is the best part of the story. On a site visit the next day after the garlic mustard was found, noxious weed program specialist Roy Brunskill noticed a lot of foot traffic on the trail between a campsite and the major trail bordering the Snoqualmie River. In addition to going over how to effectively control the weeds, Roy consulted with David Sizemore of Parks on the importance of closing the trails between the campsite and the major trail next to the garlic mustard infestation. Roy was concerned that seeds would be spread into the campsite and along the main trail, possibly creating an infestation that was not possible to contain. Parks staff took the advice seriously and within 10 days of the garlic mustard being found the plants were controlled, the adjacent trails were fenced off and signs were posted alerting park users to the problem. That’s rapid response!

Trail infested with garlic mustard closed at Tolt MacDonald Park. Photo by Roy Brunskill.

When Roy visited the site last week, the fences and posters were still up and the garlic mustard plants were all well on their way to dying. And importantly, as Roy observed, “by the amount of spider webs across the trails and the amount of loose leaf litter on the trail, no one has been on the trail for a long time”. The fences have prevented trail users and their dogs from accidentally carrying seeds to new areas and have also deterred larger wildlife from using the infested trails, greatly reducing the chance of further spread. Parks’ quick actions of control and containment are exactly what it takes to stop the spread of garlic mustard in our forests. Way to go King County Parks!

Signs at closed trail  alert public to garlic mustard infestation at Tolt MacDonald Park. Photo by Roy Brunskill.