Plants of Pseudoscleropodium purum, a moss native to central and western Europe, are well established in western, central, and eastern New York State, mainly in lawns of cemeteries, especially those with moist clayey soil, shade provided by conifers (Picea abies, Thuja occidentalis) in small groves, and periodic mowing. Male and female plants occur in Rensselaer County, New York cemeteries, but not in the same ones. Sporophytes have not been found, and reproduction appears to occur vegetatively as plants are cut and spread during lawn maintenance. If spore production is established within the naturalized range of this moss in the northeastern United States, the species may become more widespread, and possibly invasive. While the date and method of introduction into the State of New York are unknown, a 19th century specimen of P. purum from the West Coast of North America indicates that the moss may have reached that region as packing material in the late-1800’s.