Old-growth forests in the temperate deciduous zone of Quebec: Identification and evaluation for conservation and research purposes

2003 ◽  
Vol 79 (3) ◽  
pp. 559-569 ◽  
Author(s):  
Normand Villeneuve ◽  
Jacques Brisson

The Quebec Department of Natural Resources (Ministère des ressources naturelles du Québec) is working to identify and protect old-growth forests in the deciduous forest zone of the province. A total of 88 sites was visited and a multivariate analysis of the main attributes of old growth allowed the development of quantitative definitions and criteria for identifying old-growth sugar maple (Acer saccharum), eastern hemlock (Tsuga canadensis), eastern white pine (Pinus strobus), eastern white-cedar (Thuja occidentalis), and red spruce (Picea rubens) stands. Life expectancy of various species according to environment was determined through a statistical analysis of 21 500 study trees taken from the province's forest inventory. Four different identification criteria for old-growth forests were developed that include a number of indicators for old growth. Along with advanced age of forest cover, the criteria that best reflected the nature of old-growth forests were the presence of large dead trees, low cutting intensity, and the importance of shade-tolerant species. Old-growth forests identified during this validation work occupy roughly 60 km2 in Quebec's deciduous forest zone. Among other things, old-growth sugar maple stands of over 400 years old were discovered, containing stems with a diameter at breast height of 140 cm and a height of over 38 m. The very great potential of many of these exceptional forests for scientific research and biodiversity conservation is illustrated by the work carried out in the Boisé des Muir. Despite its small size, this sugar maple stand, which is over 300 years old, has advanced knowledge in fields as varied as forest dynamics, biodiversity, and climate studies, and has also served as a control site for various scientific studies. Key words: old-growth forests, definitions, criteria, indicators, inventory, Quebec, conservation, scientific value

1996 ◽  
Vol 26 (10) ◽  
pp. 1875-1892 ◽  
Author(s):  
Sally E. Dahir ◽  
Craig G. Lorimer

Trends in gap dynamics among pole, mature, and old-growth northern hardwood stands were investigated on eight sites in the Porcupine Mountains of western upper Michigan. Recent gaps (created between 1981 and 1992) were identified using permanent plot records of tree mortality, while older gaps (1940–1981) were identified using stand reconstruction techniques. Although canopy gaps were somewhat more numerous in pole and mature stands, gaps were <25% as large as those in old-growth stands because of smaller gap-maker size, and the proportion of stand area turned over in gaps was only about half as large. Gap makers in younger stands generally had mean relative diameters (ratio of gap-maker DBH to mean DBH of canopy trees) <1.0 and were disproportionately from minor species such as eastern hophornbeam (Ostryavirginiana (Mill.) K. Koch). Gap makers in old-growth stands had mean relative diameters >1.5 and were predominantly from the dominant canopy species. Even in old-growth forests, most gaps were small (mean 44 m2) and created by single trees. Based on the identity of the tallest gap tree in each gap, nearly all shade-tolerant and midtolerant species have been successful in capturing gaps, but gap capture rates for some species were significantly different from their relative density in the upper canopy. The tallest gap trees of shade-tolerant species were often formerly overtopped trees, averaging more than 60% of the mean canopy height and having mean ages of 65–149 years. Canopy turnover times, based on gap formation rates over a 50-year period, were estimated to average 128 years for old-growth stands dominated by sugar maple (Acersaccharum Marsh.) and 192 years for old-growth stands dominated by hemlock (Tsugacanadensis (L.) Carrière). While these estimates of turnover time are substantially shorter than maximum tree ages observed on these sites, they agree closely with independent data on mean canopy residence time for trees that die at the average gap-maker size of 51 cm DBH. The data support previous hypothetical explanations of the apparent discrepancy between canopy turnover times of <130 years for hardwood species and the frequent occurrence of trees exceeding 250 years of age.


Forests ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 111 ◽  
Author(s):  
Chuping Wu ◽  
Bo Jiang ◽  
Weigao Yuan ◽  
Aihua Shen ◽  
Shuzhen Yang ◽  
...  

Large-diameter trees have mainly been used for timber production in forestry practices. Recently, their critical roles played in biodiversity conservation and maintenance of ecosystem functions have been recognized. However, current forestry policy on the management of large-diameter trees is weak. As China is the biggest consumer of large-diameter timbers, how to maintain sustainable large-diameter timber resources as well as maximize ecological functions of the forests is a critical question to address. Here we summarize historical uses, distribution patterns, and management strategies of large-diameter trees in China. We found that large-diameter trees are mainly distributed in old-growth forests. Although China’s forest cover has increased rapidly in the past decades, large-diameter trees are rarely found in plantation forests and secondary forests. We suggest that knowledge of large-diameter trees should be widely disseminated in local forestry departments, especially their irreplaceable value in terms of biodiversity conservation and ecosystem functions. Protection of large-diameter trees, especially those in old-growth forests, is critical for sustainable forestry. To meet the increasing demand of large-diameter timbers, plantation forests and secondary forests should apply forest density management with thinning to cultivate more large-diameter trees.


2012 ◽  
Vol 42 (5) ◽  
pp. 899-907 ◽  
Author(s):  
Tuomas Aakala ◽  
Shawn Fraver ◽  
Brian J. Palik ◽  
Anthony W. D’Amato

Characterizing the spatial distribution of tree mortality is critical to understanding forest dynamics, but empirical studies on these patterns under old-growth conditions are rare. This rarity is due in part to low mortality rates in old-growth forests, the study of which necessitates long observation periods, and the confounding influence of tree in-growth during such time spans. Here, we studied mortality of red pine ( Pinus resinosa Ait.) in five old-growth stands in Minnesota, USA, demonstrating the use of preexisting information of cohort age structures to account for in-growth after the most recent cohort establishment. Analyses of spatial point patterns, using both Ripley’s K-function and the pair correlation function, showed that tree mortality was essentially a random process, without evidence of contagious mortality patterns that are often expected for old-growth forests. Our analyses further demonstrated in practice that the distribution of dead trees may differ from that of the tree mortality events, which are constrained to occur within the initial distribution, and how mortality patterns can shape the spatial distribution of mature living trees, often attributed to aggregated regeneration patterns. These findings emphasize the need to disentangle the influence of the initial distribution of trees from that of actual tree mortality events.


2006 ◽  
Vol 36 (9) ◽  
pp. 2235-2246 ◽  
Author(s):  
Richard A Hallett ◽  
Scott W Bailey ◽  
Stephen B Horsley ◽  
Robert P Long

Sugar maple (Acer saccharum Marsh.) decline disease on the Allegheny Plateau (region 1) resulted in high levels of mortality during the 1990s. Sugar maple was predisposed to decline because of an imbalance in Mg, Ca, and Mn nutrition and incited to decline by repeated defoliation. We sampled 33 stands in New York, Vermont, and New Hampshire (region 2) to determine if this model of sugar maple decline applies to a broader region. Low Ca and Mg and higher Mn levels were correlated with poorer tree health in both regions, but region 2 stands had little defoliation and few dead trees, suggesting that both unbalanced nutrition and stress are required for mortality to occur. We predict that stands with low foliar Ca and Mg and high Mn levels would incur increased mortality if stressed. In region 2, relationships between Ca, Mg, and Mn levels and dieback suggested that impacts on sugar maple may be caused by nutritional imbalance alone. Partial correlation analysis suggests that antagonism between Mg and Mn is the most important nutritional factor in region 1, while Mn supply is most important in region 2. We suggest that more research is needed on the interacting roles played by Ca, Mg, Al, and Mn in sugar maple performance.


2005 ◽  
Vol 64 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Brigitte Talon ◽  
Serge Payette ◽  
Louise Filion ◽  
Ann Delwaide

AbstractCharcoal particles are widespread in terrestrial and lake environments of the northern temperate and boreal biomes where they are used to reconstruct past fire events and regimes. In this study, we used botanically identified and radiocarbon-dated charcoal macrofossils in mineral soils as a paleoecological tool to reconstruct past fire activity at the stand scale. Charcoal macrofossils buried in podzolic soils by tree uprooting were analyzed to reconstruct the long-term fire history of an old-growth deciduous forest in southern Québec. Charcoal fragments were sampled from the uppermost mineral soil horizons and identified based on anatomical characters. Spruce (Picea spp.) fragments dominated the charcoal assemblage, along with relatively abundant wood fragments of sugar maple (Acer saccharum) and birch (Betula spp.), and rare fragments of pine (Pinus cf. strobus) and white cedar (Thuja canadensis). AMS radiocarbon dates from 16 charcoal fragments indicated that forest fires were widespread during the early Holocene, whereas no fires were recorded from the mid-Holocene to present. The paucity of charcoal data during this period, however, does not preclude that a fire event of lower severity may have occurred. At least eight forest fires occurred at the study site between 10,400 and 6300 cal yr B.P., with a dominance of burned conifer trees between 10,400 and 9000 cal yr B.P. and burned conifer and deciduous trees between 9000 and 6300 cal yr B.P. Based on the charcoal record, the climate at the study site was relatively dry during the early Holocene, and more humid from 6300 cal yr B.P. to present. However, it is also possible that the predominance of conifer trees in the charcoal record between 10,400 and 6300 cal yr B.P. created propitious conditions for fire spreading. The charcoal record supports inferences based on pollen influx data (Labelle, C., Richard, P.J.H. 1981. Végétation tardiglaciaire et postglaciaire au sud-est du Parc des Laurentides, Québec. Géographie Physique et Quaternaire 35, 345-359) of the early arrival of spruce and sugar maple in the study area shortly after deglaciation. We conclude that macroscopic charcoal analysis of mineral soils subjected to disturbance by tree uprooting may be a useful paleoecological tool to reconstruct long-term forest fire history at the stand scale.


2002 ◽  
Vol 19 (2) ◽  
pp. 73-79 ◽  
Author(s):  
Dale R. Bergdahl ◽  
Paul E. Sendak ◽  
Donald R. Tobi ◽  
James R. Bove ◽  
Louise M. Tritton

Abstract Sugar maples (Acer saccharum Marsh) ≥ 2.0 in. dbh were evaluated for incidence of annual canker caused by Fusarium spp. A total of 1,880 trees were evaluated from 73 plots located on 635 ac of privately owned northern hardwood forest in north central Vermont. About 12% of the trees were dead and one-fourth of both living and dead trees had annual canker. A logistic regression model was used to assess the role of soil-site characteristics related to the incidence of annual cankering. Probability estimates from the estimated regression equation were used to generate a map of annual canker risk. The generality of the results obtained here are untested and need to be applied to a more extensive area for validation. However, the technique for forest disease risk assessment could have wide application. We found annual canker was more common on sites that maintained a high number of stems per acre, on sites that were shallow to bedrock, and on sites that were dominated by sugar maple. We believe these findings suggest that sites that have shallow soils that include sugar maple probably should not be managed to encourage sugar maple. Sugar maple probably should be managed in stands that contain ample stocking of other northern hardwood species, and cultural practices that encourage maple over other species probably should be avoided.


2006 ◽  
Vol 36 (11) ◽  
pp. 2769-2779 ◽  
Author(s):  
Mark C Vanderwel ◽  
John P Caspersen ◽  
Murray E Woods

We used data from hardwood-dominated permanent sample plots in Ontario to estimate the probability of a tree falling during the 5 year period in which it dies ("tree fall"), and likewise the 5 year probability of snag fall. Tree fall probabilities ranged from 5% to 31% across species, with smaller dead trees more likely to be downed than larger ones. Expected half-lives (median time from death to fall) for 25 cm diameter snags varied from 5 to 13 years among species. Fall rates were higher for 10 cm diameter snags but relatively constant for 20–60 cm diameter snags. Recent harvesting substantially increased the probabilities of both tree fall and snag fall, with the former effect most pronounced for small individuals. We used these estimated fall rates to simulate snag dynamics in uneven-aged sugar maple (Acer saccharum Marsh.) stands. Mean snag densities were 32 and 50 snags/ha in selection-management and old-growth scenarios, respectively. Fifty-four percent of this difference was attributable to the lower density of live trees in the selection-management scenario, while 31% was attributable to losses of snags during harvesting. Silvicultural practices that strategically increase tree mortality rates, together with snag retention, as far as safety permits, during harvesting, could represent an effective approach to snag management under the selection system.


2007 ◽  
Vol 37 (1) ◽  
pp. 50-61 ◽  
Author(s):  
Tuomas Aakala ◽  
Timo Kuuluvainen ◽  
Louis De Grandpré ◽  
Sylvie Gauthier

Spatial patterns, rates, and temporal variation of standing-tree mortality were studied in unmanaged boreal old-growth forests of northeastern Quebec. The study was carried out by sampling living and dead trees within 15 transects (400 m long, 40 m wide). The transects lay in stands that were classified according to their species composition in three types: dominated by black spruce, Picea mariana (Mill.) BSP; mixed P. mariana and balsam fir, Abies balsamea (L.) Mill.; and dominated by A. balsamea. Spatial patterns were analysed using Ripley's K function. The year of death was cross-dated using 190 sample discs extracted from dead standing A. balsamea and P. mariana to assess the rates and temporal variation of mortality. The spatial patterns of standing dead trees in P. mariana stands were predominantly clustered. The spatial patterns of large dead trees (>19 cm diameter at breast height (1.3 m height; DBH)) in mixed and A. balsamea-dominated stands were mainly random, with few stands showing clustered patterns. Small dead trees (9–19 cm DBH) in these stands were generally more clustered than larger trees. Tree mortality varied from year to year, though some mortality was observed in all the studied stand types for almost every year. Standing trees that had recently died accounted for 62%, 48%, and 51% of overall mortality in P. mariana-dominated, mixed, and A. balsamea-dominated stands, respectively. The results of this study indicate that mortality of standing trees outside of episodic mortality events (such as insect outbreaks) is an important process in the creation of structural complexity and habitat diversity in these stands.


2008 ◽  
Vol 255 (3-4) ◽  
pp. 410-420 ◽  
Author(s):  
Tuomas Aakala ◽  
Timo Kuuluvainen ◽  
Sylvie Gauthier ◽  
Louis De Grandpré

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