A comparison of pre-European settlement (1857) and current (1981-1995) forest composition in central Ontario

To better manage southern Ontario's natural forests, the former and present status of old growth must be understood. We hypothesize that old-growth pine (Pinus spp.), although dominant elsewhere, was less common in southern Ontario than popular history suggests: we are obliged to evaluate historical information that has been filtered both by the original compilers and through our own biases. Beginning around 600 AD, the predominant beech (Fagus americana) forest was partially replaced by maple (primarily Acer saccharum), oaks (Quercus spp.) and eastern white pine (P. strobus). This pine increase either followed abandonment of pre-Columbian agriculture or, more plausibly, accompanied climate cooling. Eighteenth and 19 th century European settlers encountered abundant large trees, which they hewed for square pine timber, milled timber, and tanbark. Other stands were cut and burned for agricultural clearance, with a potash by-product. Until recently, Ontario research emphasized the old-growth pine stands of central and northern Ontario to the relative exclusion of other kinds of old forest because very few southern Ontario old-growth stands remained to study. Ontario forest resource inventory data (FRI) show stands of over 150 years totalling only 1475 ha in 1978, concentrated on the Oak Ridges Moraine, the St. Lawrence Valley and the Awenda Peninsula. Red (P. resinosa) and eastern white pine stands constituted only 5.3% of the 1978 forested area, with virtually none of over 150 years, whereas eastern hemlock (Tsuga canadensis) stands constituted 12.8%. The difficulty in finding modern old growth necessitates historical reconstruction using physical, written and graphical resources, including early survey records and trade statistics. In a case study of 1822 survey data from Darling Township (Lanark Co.) and 1960 FRI, vegetation was classified using TWINSPAN and mapped using ARC/INFO Thiessen polygons. In 1822, dominant hemlock occupied half the township but it has since been eliminated as a dominant. Conversely, there were no pine-dominated forests in 1822, but these had increased to 16% of the area by 1960. A second case used similar methods, with 1855 data for St. Edmunds and Lindsay townships (Bruce Co.) and 1981 FRI. Although logging halved the area and reduced the stature of pines in the large pinery, the elimination of dominant hemlock (originally 41% by area) is more significant. Fragmentary square timber trade data suggest that at least half the large pines in Bruce County were in St. Edmunds, so pine must have been spectacularly concentrated in a few areas. The third case, a map constructed from Gourlay's 1817-1819 survey, also demonstrates that pine-dominated areas were in the minority in southern Ontario, concentrated on sandy soils around Lakes Ontario and Erie. However, big hemlocks, beeches, maples and oaks were much more common overall. Management responses to this information should include designation of older southern Ontario forest stands (especially those never cleared since settlement) for mat...

Section: Current Status Of Old Growth In Southern Ontariomentioning

confidence: 99%

Presettlement forest in southern Ontario: Ecosystems measured through a cultural prism

Suffling¹,

Evans²,

Perera³

2003

“…Several studies have indicated that the composition of Ontario's forests have been significantly altered (boreal forest: Brumelis and Carleton 1988, Hearndon et al 1992, Carleton and MacLellan 1994; Great Lakes-St. Lawrence forest: Jackson et al 2000). For instance, according to Hearndon et al (1992) and Jackson et al (2000), industrial logging of conifer stands in Ontario's forests has resulted in widespread regeneration of intolerant hardwoods, despite attempts to establish conifers.…”

Section: Gaining Awareness Of Old-growth Forests In Ontariomentioning

confidence: 99%

“…For instance, according to Hearndon et al (1992) and Jackson et al (2000), industrial logging of conifer stands in Ontario's forests has resulted in widespread regeneration of intolerant hardwoods, despite attempts to establish conifers. Carleton and MacLellan (1994) suggest that advances in fire suppression measures over the past several decades have reduced the number of early successional, post-fire, conifer-dominated stands in northeastern Ontario.…”

Section: Gaining Awareness Of Old-growth Forests In Ontariomentioning

confidence: 99%

Adapting forestry practices to address old-growth concerns in the Great LakesSt.Lawrence forests of Ontario

Pinto¹

2003

Self Cite

The Great Lakes-St. Lawrence forest, particularly the eastern white (Pinus strobus L.) and red pine (P. resinosa Ait.) forests around Temagami and Sault Ste. Marie, was the centre of controversy regarding the treatment of old-growth forests in Ontario in the 1980s and 1990s. The controversy stemmed from changes in forest composition and structure occurring in the forest. For example, the Ontario public was concerned with the obvious reduction in numbers of large eastern white and red pine trees and their replacement with small, often poor quality, white birch (Betula papyrifera Marsh.), aspen (Populus tremuloides Michx.), and jack pine (Pinus banksiana Lamb.) trees. Over the past two decades, changes in legislation, forest planning and stand prescriptions have been made in Ontario and practices at the forest and stand levels have also changed significantly. The new practices are based on linking forest activities to a better understanding of ecological processes in the forest; in particular, linking harvest and regeneration activities to our current understanding of natural disturbances and plant adaptations. These practices attempt to match more closely the conditions found in forests with a heritage of natural disturbance and reproduction, i.e., old-growth forests. For example, stand-initiating disturbances result in some trees being killed, some being damaged, and some surviving. The new harvest practices consider tree adaptations and site factors when deciding whether a tree will be cut or not. This paper provides examples of how this ecosystem-based forestry is being applied in Ontario.

“…In the 1980s and 90s, many stands were harvested using the selection silviculture system because it was viewed as the most ecologically sustainable solution for managing hardwood forests even when site productivity, species composition, and forest structure were not suited to this approach. The prevalence of small canopy gap disturbances associated with selection harvesting led to a persistence of shade-tolerant hardwoods within the GLSL region (Jackson et al 2000). The continued loss of mid-tolerant species, such as yellow birch (Betula allegheniensis Britt.…”

Section: Introductionmentioning

confidence: 99%

Comparative effects of full-tree and tree-length shelterwood harvesting on residual tree damage and coarse woody debris volume in the Great Lakes – St. Lawrence forest

Jones

McPherson

2012

Residual stand damage and coarse woody debris loads were evaluated in 15 hardwood and white pine uniform shelterwood harvest blocks, in the Great Lakes -St. Lawrence Forest Region, using tree-length (TL) and full-tree (FT) harvesting techniques. Stand-level damage rates to residual stems in both the TL and FT harvest operations were below Ontario's allowable "major" damage limits of 15% to all residual trees and 10% to acceptable growing stock (AGS) trees. No significant differences in damage rates were observed between the TL and FT harvest systems and were comparable to past assessments in TL and FT harvested blocks. Despite efforts to increase utilization of material from these study sites, no significant differences were observed in coarse woody debris (CWD) volume or the distribution of that volume across decay classes.Key words: full-tree harvesting, hardwoods, white pine, shelterwood silviculture, coarse woody debris, logging damage RÉSUMÉOn a évalué les blessures aux arbres résiduels et la quantité de débris ligneux grossiers dans 15 blocs de coupes progressives uniformes de feuillus et de pin blanc situés dans la région forestière des Grands Lacs et du Saint-Laurent utilisant les techniques de récolte par arbres en longueur (TL) et par arbres entiers (AE). Les taux de blessures aux arbres résiduels dans l' ensemble du peuplement, tant dans les opérations de TL que d' AE, se situaient sous les limites permises en Ontario pour les blessures « importantes » soit 15 % pour tous les arbres résiduels et de 10 % pour les arbres formant le stock sur pied acceptable (SPA). Aucune différence significative dans les taux de blessures n'a été observée entre les systèmes de récolte par TL et par AE et ces taux étaient comparables aux évaluations antérieures pour des blocs récoltes par TL et par AE. Malgré des efforts pour accroître l'utilisation de la matière ligneuse tirée de ces sites d' étude, aucune différence significative n'a été observée dans le volume de débris ligneux grossiers et dans sa répartition parmi les classes de décomposition.