Effect of cutting intensity on microenvironmental conditions and regeneration dynamics in yellow birch – conifer stands

Abstract

This paper presents the 5 year results of different cutting intensities (removal of 0%, 40%, 50%, 60%, and 100% of the basal area) applied in two mixed yellow birch ( Betula alleghaniensis Britt.) – conifer stands of eastern Quebec, Canada. Two sites 90 km apart were used: Armagh and Duchesnay. Each site had four replicates of the treatments in a randomized block design. The effect on light availability was similar in the two sites: the 0%, 40%, 50%, 60%, and 100% cuts transmitting a mean of 5%, 21%, 26%, 30%, and 94% of full light, respectively, during the first summer. Soil temperature increased only in the 100% cut (4−5 °C, maximum daily temperature). Soil disturbance during harvest was higher at Duchesnay than at Armagh, which clearly improved seedbed receptivity, particularly to yellow birch. After 5 years, treated areas contained 21 000 to 48 300 seedlings/ha at Duchesnay compared with 5500 – 10 500 seedlings/ha at Armagh. Significant losses of coniferous advance growth were observed at both sites, but a subsequent seedling recruitment occurred only at Duchesnay. Red spruce ( Picea rubens Sarg.) showed superior establishment in the 60% cut (4400 seedlings/ha) than under other cutting intensities (1600–2100 seedlings/ha), whereas balsam fir ( Abies balsamea (L.) Mill.) responded well to all partial cutting treatments. At both sites, pin cherry ( Prunus pensylvanica L.f.) was the main competing species in the 100% cut, whereas densities of the preestablished mountain maple ( Acer spicatum Lamb.) and striped maple ( Acer pensylvanicum L.) either remained the same or increased in the partial cuts.

Effect of gap size, aspect and slope on available light and soil temperature after patch-selection cutting in yellow birch–conifer stands, Quebec, Canada

“…conditions in other yellow birch-conifer stands (Prévost, 2008). Despite the low levels of light availability, the analyses revealed that pre-cut PPFD was related to the planned blocks, with three times more light in blocks B and D than in block C. Block B was oriented east-southeast and this may explain why the understory received more direct sunlight than in block C which was oriented northeast.…”

Change from pre-settlement to present-day forest composition reconstructed from early land survey records in eastern Québec, Canada

“…The onset of large-scale industrial clear-cutting for sawmills and the pulp and paper industry at the end of the 19th century appears to have been the cause behind the reduction in conifer dominance and their replacement by deciduous tree species (Boucher et al 2006;Etheridge et al 2006). By clearing large expanses of the landscape, clearcuts are known to encourage invasion by fast-growing species such as aspen, paper birch, maple, wild cherry, hazelnut, willow and alder (Harvey & Bergeron 1989;Archambault et al 1998;Aubin et al 2005;Prévost 2008). In our study, eastern white cedar was the taxon that had decreased the most in dominance since pre-settlement times.…”

Seed Rain and Seedling Establishment of Picea glauca and Abies balsamea after Partial Cutting in Plantations and Natural Stands

“…Our results suggest that partial cutting promotes seed germination and seedling development. In the northern temperate and boreal forests of Eastern Canada, mainly composed of fir and spruce species, fir seedlings reach densities greater than 35,000 seedlings/ha while spruce only reach 1000 to 3000 seedlings/ha [1,22,39]. In mixed natural stands found elsewhere in the world, the genus Abies is often the one that regenerates most easily when co-occurring with other species [40,41].…”

“…Our results indicate that the natural establishment of seedlings is relatively limited in plantations compared to natural stands. This suggests that certain factors favorable to the establishment of regeneration such as substrate type [8,11,23], light [39,42,43], stand structure [44] and seed trees [41] might be more limiting in plantations than in natural stands. The plantations examined in this study were established on abandoned agricultural lands that had been farmed for decades.…”