FPC is responsible for brushing all 47 miles of soft-surface trails in Forest Park, a massive undertaking that we tackle each summer. Brushing is a trail maintenance act that involves the removal of excess vegetation and debris from the trails. Now that we are in the latter part of the summer, our Trails Manager, Ingry Thurow, has provided some updates on where we are in the brushing season and why this work is important.
- How’s our 2022 brushing plan going?
We have just under 19 miles to go out of the total 47 miles of soft-surface trails in Forest Park! Big thanks to our volunteers for making this happen. This year, more of our brushing plan than ever before is being completed by volunteers, with staff-only brushing work days kept to a minimum. Our stewardship program is strong enough now that we can rely more heavily on volunteers – but we still need your help if you want to give back to Forest Park’s trails this summer!
- Wait, you cut back the vegetation on the trails in Forest Park? Why would you do that?
In short: to keep our trails sustainable, to reduce erosion, and to improve and maintain safety for trail users.
Did you know that the most reliable trail maintenance happens year-round at all hours of the day, just from the way that people use trails? In highly trafficked areas like Forest Park, cyclists, runners, dog walkers, and hikers maintain the trail system just by the way they use it. When people use the very outside edge of the trail (say, to avoid a branch or a stalk of stinging nettle hanging from the uphill side) over time that section of trail will erode and shift downhill, in a process called “trail creep.” You might have seen this in action on certain trails in the park – in the early to mid stages of trail creep, it will look like there are two trails right next to each other, one slightly higher and one slightly lower. Over time these areas tend to become eroded, muddy, and more prone to failures like small landslides.
A big part – maybe the central part – of a trail worker’s job is to guide trail users in very subtle ways that protect the integrity of the trail and the habitat around it. This is the goal with brushing: by trimming back vegetation, we create a “brushing corridor.” Think of a hallway through the forest created by the negative space between plants and trees. When we maintain that corridor via our summer brushing plan, we shift the center of that corridor slightly uphill, or to the “inside” corner of the trail. In other words, we trim back farther on the uphill side than the downhill side, to discourage people from eroding the trail edge.
- Won’t removing plants promote erosion rather than slowing or stopping it?
This is a great question and a common concern, but you have nothing to fear. We never leave bare soil behind when we brush. In fact, we aim to leave about 5-6″ of vegetation along the trailside since we love our native plants and leaving them helps to reduce erosion. We do sometimes use handsaws to remove small trees that encroach too closely on the corridor, such as the fast-growing red elderberry that is so ubiquitous in Forest Park.
By strategically removing vegetation along the trail, we ensure that users walk where trail workers want them to. Our trails allow large numbers of people to connect with this special place, while concentrating the erosive impact of their feet and bicycle tires onto areas designed and built to handle it.
Have additional questions about trail work? Send an email to Ingry.
Want to get involved? Take a peek at our Event Calendar and find a time that works for you to join us! Our trail work parties are fun, social, meditative and rewarding.
Worried about working in the heat? All of our August work parties are in the morning (9am-12pm), and FPC event leaders check in often with our volunteers, who can take off a little early if need be. The good news is that Forest Park is one of the coolest places in Portland to hang out during hot summer days.