In North America, this widely scattered diploid (2n = 14) winter annual (flowering mostly Mar-Apr in Ky.) appears to have been virtually unknown before Pennell (1935; see also F), appearing first on ballast at ports. All Ky. records of polita date from after 1970. It is easily confused with agrestis or persica, and colls. from Ky. deserve to be rechecked (Abbott et al. 2004). The three species occur in similar habitats: lawns and other frequently disturbed low vegetation, usually in sun and on more or less eutrophic soils.