This paper highlights the need for a new power model for skid-steered wheeled robots driving on loose soil, and lays the groundwork to develop such a model. State-of-the-art power modeling assumes hard ground; under typical assumptions, this predicts constant power consumption over a range of small turning radii where the inner wheels rotate backwards. However, experimental results performed both in the field and in a controlled laboratory show that, on sand, power is not in fact constant with respect to turning radius in this case. Power peaks in a newly identified range of turns where the inner wheels rotate backwards but are dragged forward. Data shows higher motor torque and wheel sinkage in this range. A skidding wheel that is sunk into loose soil bulldozes a pile of sand; initial modeling of this phenomenon reproduces the trend in additional power with respect to turning radius. As work on a full power model for loose soil continues, this work identifies turning radii to avoid whenever possible in practice.