  Polarization is a powerful tool for understanding stellar atmospheres and
circumstellar environments. Mira and semi-regular variable stars have been
observed for decades and some are known to be polarimetrically variable,
however, the semi-regular variable V Canes Venatici displays an unusually
large, unexplained amount of polarization. We present ten years of optical
polarization observations obtained with the HPOL instrument, supplemented by
published observations spanning a total interval of about forty years for V
CVn. We find that V CVn shows large polarization variations ranging from 1 -
6%. We also find that for the past forty years the position angle measured for
V CVn has been virtually constant suggesting a long-term, stable, asymmetric
structure about the star. We suggest that this asymmetry is caused by the
presence of a stellar wind bow shock and tail, consistent with the star's large
space velocity.
