TITLE:
Exploring Factors Influencing Species Natural Regeneration Response Following Harvesting in the Acadian Forests of New Brunswick
AUTHORS:
Lee Salmon, John A. Kershaw Jr., Anthony R. Taylor, Marek Krasowski, Michael B. Lavigne
KEYWORDS:
Tolerant Hardwood Management, Regeneration Dynamics, Time Since Harvest, Opening Size, Residual Overstory, Acadian Forest Region, Regression Trees
JOURNAL NAME:
Open Journal of Forestry,
Vol.6 No.3,
June
22,
2016
ABSTRACT: In the Acadian Forest
Region of northeastern North America, forest managers are under increasing
public pressure to restore the forest to a more historic, natural condition by
reducing in clearcutting and promoting partial-cut treatments that more closely
emulate historic, local natural disturbance regimes. However, although numerous
studies on the effects of partial-cutting on forest regeneration response have
been conducted in surrounding temperate and boreal forest ecosystems, there are
few studies that directly explore responses to various forms of harvesting
within the Acadian Forest ecosystem, with its unique mixture of northern hardwoods and boreal forest species. Here, we
conducted one of the first retrospective studies on forest regeneration
following a variety of harvesting methods in the Acadian Forest using univariate
and multivariate regression trees to assess regeneration response in 50
naturally-regenerating, harvested forest sites in New Brunswick, Canada. Our
study shows that regeneration
was highly influenced by harvest type, overstory composition, and environmental
conditions as reflected by ecoregion classification. Canopy opening size
(as controlled by harvest method) significantly influenced the dominance of
regenerating species. The presence of conspecific overstory trees increased the
likelihood of their regeneration following disturbance, supporting the
direct-regeneration hypothesis, especially for species with limited seed
dispersal (e.g., sugar maple (Acer
saccharum Marsh.) and American beech (Fagus
grandifolia Ehrh.). Despite reported problems elsewhere in eastern North
America, neither American beech nor balsam fir (Abies balsamea (L.) Mill.) constituted significant competition for
the desired species on a broad scale, but the presence of beech was a
significant deterrent for yellow birch (Betula
alleghaniensis Britt.).