  We consider the phase ordering dynamics of an isolated quasi-two-dimensional
spin-1 Bose gas quenched into an easy-plane ferromagnetic phase. Preparing the
initial system in an unmagnetized anti-ferromagnetic state the subsequent
ordering involves both polar core and Mermin-Ho spin vortices, with the ratio
between the different vortices controllable by the quench parameter.
Ferromagnetic domain growth occurs as these vortices annihilate. The distinct
dynamics of the two types of vortices means that the domain growth law is
determined by two macroscopic length scales, violating the standard dynamic
scaling hypothesis. Nevertheless we find that universality of the ordering
process manifests in the decay laws for the spin vortices.
