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The recurring role of site challenges contemporary theories about regeneration under selection systems in northern hardwoods

Publication: Canadian Journal of Forest Research
15 September 2021


In naturally regenerated managed forests, silvicultural methods leverage timing and intensity of harvesting activities to align with species-specific reproduction mechanisms. With contemporary emphasis on complex stand structure and diverse composition, there is uncertainty in the continued use of timber-oriented management practices in meeting evolving objectives. In the northern hardwood region of North America, contemporary theory is that selection regeneration systems result in homogenization of structure and composition through increasing dominance of Acer saccharum Marsh. Given the coupling of soils and vegetation in northern hardwoods, trends in site conditions that may be more resilient and (or) facilitative to community diversity may be of value to silviculturists. Remote-sensing products and inventory records were integrated to assess tree communities across site variables in northern Michigan, USA. The results reveal that composition is stabilized by local landforms and that diversity increases with hydrologic catchment area. Time since treatment (1–54 years) appeared negatively correlated with catchment area, reflecting lowlands with high diversity not managed or harvested infrequently, due to equipment access and operational logistics. Broad interpretations of selection regeneration systems may be invalidated by the influence of site conditions not previously accounted for, and the results highlight a novel technique to capture the effect of topography on species assemblages.


Dans les forêts aménagées qui sont naturellement régénérées, les méthodes sylvicoles ajustent le calendrier et l’intensité des activités de récolte pour qu’elles concordent avec les mécanismes de reproduction des espèces. Puisqu’on met présentement l’accent sur la complexité de la structure des peuplements et la diversité de leur composition, il n’est pas certain que de continuer à utiliser des pratiques d’aménagement axées sur la production de bois permette d’atteindre des objectifs en évolution. Dans la région des feuillus nordiques de l’Amérique du Nord, la théorie contemporaine veut que les systèmes de régénération par jardinage mènent à une homogénéisation de la structure et de la composition à cause de la dominance croissante d’Acer saccharum Marsh. Parce que les sols et la végétation sont intimement liés dans les peuplements de feuillus nordiques, les tendances faisant en sorte que les conditions de la station peuvent être plus résilientes ou facilitantes pour la diversité de la communauté pourraient être utiles aux sylviculteurs. Des outils de télédétection et des données d’inventaire ont été intégrés pour évaluer les communautés forestières selon une gamme de variables de la station dans le nord du Michigan, aux États-Unis. Les résultats révèlent que la composition est stabilisée par les reliefs locaux et que la diversité augmente avec la superficie du bassin versant. Le temps écoulé depuis l’application d’un traitement (entre 1 et 54 ans) est apparu négativement corrélé à la superficie du bassin versant, reflétant que les basses terres où la diversité est élevée ne sont pas aménagées ou rarement récoltées en raison de l’accès des équipements et de la logistique opérationnelle. L’interprétation générale des systèmes de régénération par jardinage peut être invalidée par l’influence des conditions de la station qui n’ont pas été prises en compte auparavant, et les résultats mettent en évidence une nouvelle technique pour détecter l’effet de la topographie sur les assemblages d’espèces. [Traduit par la Rédaction]

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cover image Canadian Journal of Forest Research
Canadian Journal of Forest Research
Volume 52Number 4April 2022
Pages: 463 - 473


Received: 21 June 2021
Accepted: 10 September 2021
Accepted manuscript online: 15 September 2021
Version of record online: 15 September 2021


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Key Words

  1. northern hardwoods
  2. single-tree selection
  3. group selection
  4. site
  5. silviculture


  1. feuillus nordiques
  2. jardinage par pied d’arbre
  3. jardinage par groupe
  4. station
  5. sylviculture



M.I. Premer [email protected]
Research, Productivity, and Sustainability, Rayonier U.S. Forest Resources, 3033 Ingram Street, Hoquiam, WA 98550, USA.
R.E. Froese*
School of Forest Science and Management, University of Alberta, 751 General Services Building, Edmonton, AB T6G 2H1, Canada.


R.E. Froese served as an Associate Editor at the time of manuscript review and acceptance; peer review and editorial decisions regarding this manuscript were handled by Joseph Antos.

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1. Long-term stability of northern hardwoods across a topographic gradient and variations in harvest methods

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