Crataegus in the northeastern and central United States and adjacent Canada

  title={Crataegus in the northeastern and central United States and adjacent Canada},
  author={Ernest Jesse Palmer},
  • E. Palmer
  • Published 6 September 1946
  • Biology
  • Brittonia
In the preparation of a revised treatment of the genus Crcataegus in the northeastern United States and adjacent Canada, to be published soon, it has been found necessary to propose a new specific name to replace one invalidated by all earlier homonym and to change the status of a number of names from species to varieties or forms. And in treating the species under a broader concept than that of the original authors, many names are placed in synonymy. This more conservative treatment of the… 
On the Origin of the Field Plants of the Northeastern United States
  • P. Marks
  • Environmental Science
    The American Naturalist
  • 1983
Old fields have dominated studies of terrestrial plant succession in the eastern United States. In spite of the tremendous amount of work on old field succession, fundamental questions remain. One
Cytological, morphological, ecological and phenological support for specific status of Crataegus suksdorfii (Rosaceae).
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New alignments in North American Crataegus (Rosaceae)
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Polyploidy, reproductive biology, and Rosaceae: understanding evolution and making classifications
It appears that hybridization, pseudogamous gametophytic apomixis, polyploidy, and self-compatibility are closely linked in Rosaceous genera Pyreae.