Tuesday, February 1, 2011

Route Finding in the Northwest Cascades

Clear cut with young Douglas fir

My work often means traversing rough ground. Assessing geology hazards entails having to get to slopes that may be unstable. That often means crossing very steep slopes. But even mild slopes pose a problem depending on the vegetation. Before heading out on any trip I check as many air photo images I can get a hold of both current and old. And if available I'll scrutinize LIDAR images. Part of that review of images is to identify potential unstable slopes and landslides, but it also allows me to scheme out possible routes.

The above clear cut looks like an easy walk at a glance. But on further careful looking it is not a very good route.

The clear cut has plenty of strands of blackberry brambles. A walk through this area will have you ending up like Steve McQueen at the end of the Great Escape tangles up in brambles versus barbed wire. In addition, older clear cuts like the one above typically will be partially covered by old rotting tree branches. They provide terrible footing as one walks across not the ground but branches that break such that one is always a bit off balanced. So even though the distance was twice as long on a recent hike, I opted for going down into the canyon in question via a forested slope.

Douglas fir/western hemlock second growth forest

I also keep an eye out for trails. Timber managers will often develop established trail routes along edges of harvest units as they survey harvest boundaries. Wildlife as well will find the easy routes and develop trail routes. The subtle trails may not get me directly to where I want to go but can save lots of time getting past tricky areas that a direct route would be much more time consuming or painful.

Deer trail on very steep slope

Wildlife trail traversing a steep slope

I followed the above wildlife trail along slopes that exceeded 45 degrees for nearly a mile on a recent trip in the Northwest Cascades. I would deviate off the trail down to places I wanted to see in the canyon floor, but always found the trail again when I headed back up the slope to get around impassible cliffs or slide areas. Elk trails can be several feet wide.

Flat ground along flood plain areas of creeks can be very rough going as well. Boulders and logs as well as thick vegetation can take a long time to push through. A long time ago I decided it was a lot easier and safer to simply walk in the creek as they provide excellent trails if you don't mind a little water. 
Flood plain along creek bottom land

Wide open trail through the forest - just a little wet


Anne Jefferson said...

This brings back many memories of field work in the Oregon Cascades. Clearcuts were miserable unless you could find a trail around it. Streams were easier than bottom lands. And the rhododendron were simply impossible on slopes.

Dan McShane said...

Anne - Rhododendron/evergreen huckleberry/salal understory if it is mature is impossible. Don't encounter very often except in a few areas on the northeast side of the Olympics. I have heard that laurel thickets in the Great Smokies are near impossible as well.