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Providing evidence to improve practice

Individual study: Regeneration of Populus nine years after variable retention harvest in boreal mixedwood forests

Published source details

Gradowski T., Lieffers V.J., Landhäusser S.M., Sidders D., Volney J. & Spence J.R. (2010) Regeneration of Populus nine years after variable retention harvest in boreal mixedwood forests. Forest ecology and management, 259, 383-389


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use partial retention harvesting instead of clearcutting Forest Conservation

A replicated, controlled study in 1999-2007 in boreal mixed wood forest in Alberta, Canada (Gradowski et al. 2010) found that low logging intensity levels decreased young tree density compared with clearcutting. Young tree density for the dominant species trembling aspen Populus tremuloides and balsam poplar Populus balsamifera was higher in clearcutt plots (15,000/ha) than in 50% (7,000) and 75% tree area retention sites (3,000), and higher in 10% (12,000) than in 75% tree retention sites. In 20% retention sites, density was similar to all other retention levels (9,000). Each of five logging intensity levels: clearcutting (0%), 10%, 20%, 50% and 75% of the area retained were applied in nine 10 ha forest compartments. Regeneration of trembling aspen and balsam poplar was assessed using six 2 × 10 m plots in each compartment (total of 270 plots).