Mateusz Korbik, Dawid Andrzejczak, Agata Jędrzejuk
New names for Schreiner and Stout poplar hybrids, trees of major importance in forestry and landscaping
Dendrobiology 2026, vol. 96: 54-66
https://doi.org/10.12657/denbio.096.005
Abstract:
Among the widely cultivated poplars, some of the most significant are those developed by Ernst J. Schreiner and Arlow B. Stout. These poplars were developed through controlled hybridization in the United States in the early 20th century, and the selected clones were efficiently distributed worldwide over the following decades. Despite their apparent prevalence in cultivation, their identification remains a significant challenge. Among the most frequently grown Schreiner and Stout clones are those derived from the crosses Populus suaveolens × P. trichocarpa and P. suaveolens × P. ×berolinensis. However, formal names were never proposed for these hybrids; consequently, they must be assigned to individual clones, further complicating their nomenclature. In this paper, based on historical data, morphological studies, and anatomical analyses of leaf petioles, it is demonstrated that these hybrids possess distinct characteristics that facilitate easy identification. Two new nothospecies, Populus ×schreineri and Populus ×stoutii are proposed and described. Both taxa exhibit clear hybrid traits; however, P. ×schreineri is morphologically closer to P. suaveolens (sect. Tacamahaca), while P. ×stoutii shows a distinct influence from the black poplar section (sect. Aigeiros). The main diagnostic features enabling their identification are highlighted, with particular emphasis on the petiole anatomy.
Keywords: identification, intrasectional hybridization, anatomical traits, new nothospecies