A post auger is a two-man, mechanical hole digger. Hand-held post augers are used during construction and farming jobs that are too big for manual post hole diggers. A fence post auger is designed to dig a hole by moving dirt from the bottom of the hole to the surface. Sometimes when digging through rocky or forested terrain a post auger will become stuck on objects that can't be seen from the surface.
Fence post augers dig holes faster than a manual post digger, but they can become stuck quite often. Repositioning the auger may loosen it enough to pull it from the ground. If that doesn't do the trick nothing beats a shovel.
Look for root causes
Examine the ground, looking for tree stumps that indicate root systems are underground near the hole and stuck auger. Post augers can become hung-up on roots and rocks, even if they seem to be small. Start the fence post auger and allow it to idle.
Grasp the fence post auger with your palms under the handles and thumbs placed on top. Press the hand lever to start spinning the auger blade. Tilt the auger forwards and backwards, and then side to side. Essentially you are widening the base of the hole to allow the auger to be pulled out.
Determine which way the resistance is coming from. A post auger digs by bringing dirt, rocks and roots to the surface. It is likely that a jam occurred during that process. Tilting the auger in the opposite direction of the jam will free it in most situations.
If none of these remedies work, dig the auger out with a shovel. Start on one side and dig at a slant toward the auger bit. Remove dirt from the edge of the auger to about six inches away from it. Stay next to the drill blade while digging. Remove rocks bigger than a golf ball.
Use an axe to free the drill blade from underground roots. Chop out the edges that are preventing the auger from drilling. Roots bigger than 2 inches wide can cause the auger to become stuck.