Stony soil auger

The auger for stony soil is heavier and more robust than the other auger types. The auger has slightly protruding angled points that curve in towards each other (see figure). They form a more or less enclosed auger body but don’t actually come in contact with each other. This creates a certain flexibility. The points cut downwards during the augering process. Stones that are encountered are wedged in between the auger blades, while the slightly finer soil (coarse sand with fine gravel) also stays in the auger.