We examined nest site selection by foundresses of the polygyne form of Solenopsis invicta. In the laboratorY, foundresses were allowed to nest in control soil vs. soil inoculated with refuse from a colony of Pheidole dentata, a natural enemy. In a second experiment foundresses chose between control and S. invicta soil. More foundresses (100%) avoided the soil of a natural enemy than the soil of a conspecific colony (79%) that may accept them into the nest. Foundresses from this polygyne ant appear to avoid other colonies in general, but avoid heterospecific colonies more.