Week in the Woods (http://weekinthewoods.org/) is a week long camp held in old growth forest on state land outside of Fairbanks, Alaska. The majority of the photos in this Instructable are from Week in the Woods and were taken by Alex Kamerling. A few photos are from second growth forest in Fairbanks and were taken by Jesse Hensel and John Manthei.
Step 1: Location and Tools
All spruce trees have workable roots. However in many places the roots are too tangled to be easily harvested. Ideal harvesting locations are eroding river banks and mixed old growth forest.
Look for an area that has both birch and spruce trees, an open canopy, and a natural unkept understory. Look for long straight lines of moss across the forest floor. Peel back a little moss and ideally you will find the rotting bark of a long dead tree.