A pair of pipe wrenches is needed to add and remove lengths of shaft. Probes work well in moist, medium textured soils that are free of gravel, stones, and dense layers. Under these conditions, the soil can be examined faster than with an auger. Probes are very difficult to use in dry, dense, or poorly graded soil, and in soil containing gravel or stones. Probes disturb the soil less than augers, but they retrieve less soil for examination.
Probes are light and easily carried, and they pull from the hole more easily than screw augers.
Often a special punch or dowel must be used to clear the tube. Use of a soil probe is the fastest method to collect samples of surface layers for analysis. The use of power equipment results in large savings in time and permits deeper and larger excavations with better exposure of the various horizons than can be attained with hand tools. Not all sites, however, are accessible to power equipment. Most of this equipment is powered by the motor of the tractor or truck on which the equipment is mounted, although some of the heavier types have separate power units.