How to Execute an Extended Column Test: While the compression test looks at fracture initiation (is it going to crack?) the extended column test looks propagation propensity (is the fracture going to propagate across the slope). Like the compression test, this test is valid for four-finger or harder (so 4F, 1F, P, K, I) snow up to 100 cm deep. If there is a layer in question that is 100 cm deep, you can isolate the column up to 120 cm in order to test the layer at 100. Isolate a 30cm upslope x 90cm wide column, isolate 15 to 120cm deep. Place shovel blade on top of the column. Tap ten times from the wrist, ten times from the elbow, ten times from the shoulder (10-10-10). Look for any fractures AND propagation. Fracture being a crack and propagation being the crack shoots across the entire column. Grab the column and jiggle it. How does it feel? Read "Making sense of snow stability tests and how they fit into tour planning" by BCA ambassador Josh Kling to learn more.
