We introduce a rank 3 geometry for any Ree group over a not necessarily
perfect field and show that its full collineation group is the automorphism
group of the corresponding Ree group. A similar result holds for two rank 2
geometries obtained as a truncation of this rank 3 geometry. As an application,
we show that a polarity in any Moufang generalized hexagon is unambiguously
determined by its set of absolute points, or equivalently, its set of absolute
lines.