Notes on Upper Skagit Complex Fire

Yet another fire area from the 2015 wildfire season. The Upper Skagit Complex took place in forest. It burned up the Skagit River gorge along both sides of the highway. Hence, a drive over the North Cascades Highway will take you through the path of a forest fire. (Note Highway 20 over Sherman Pass east of Republic passes through a forest fire burn from a 1990s fire through a larch forest).   

 

My windshield was not particularly clean

The fire path and the view shown above is a good lesson in understanding how fire passes through a forest. The intensity of the fire varies a great deal. Many trees do not burn at all. Wet areas will survive the flames as will areas when the fire burns through an area at night.

This section of the fire burned into the rock large landslide that close the highway a few years back. The newish young red alders just above the highway were untouched, but upslope the fire must have been hot with had burning of the forest despite the rocky ground.

Most of this slope burned with some sections very intensely burned. But even then stands of green remain.

These trees appear to have survived, but despite the lack of understory on the talus slope their trunks were singed.

This area adjacent to the road burned, but the burn was along the ground. My understanding of this fire via reports from on the ground was that a fair bit of slow burning took place within the ground mass of the forest. Roots of the trees burned slowly for days and then the trees fell over, rolling down the slope. Indeed I noted lots of logs that appeared to be recent tree falls along the road as well as marks on the pavement indicating log falls on the highway.

The town of Newhalem with Newhalen Creek valley behind.

Newhalem is a company town owned by Seattle City Light as part of the Skagit River hydroelectric system owned and operated by Seattle. The fire burned around the town in part due to fire response efforts.

The late August storm event put this fire out. A remarkable storm. Most typical years this fire would have continued burning all the way until steady falls rains arrived.

The fire extent was not remarkable in area for this section of the North Cascades although the more fire prone areas are a typically a bit further east. Additional fires burned in more out of the way places further up the Skagit Valley this year with one fire reburning an area burned just a few years ago.

A good take away from this fire for those passing through is that acreage or square mile burned reports do not account for the fact that these burn areas are only partially burned. What will remain is a mixed age stand of trees with standing dead timber. By some measures a healthy ecosystem.