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Individual study: Thinning and prescribed fire effects on overstory tree and snag structure in dry coniferous forests of the interior Pacific Northwest

Published source details

Harrod R.J., Peterson D.W., Povak N.A. & Dodson E.K. (2009) Thinning and prescribed fire effects on overstory tree and snag structure in dry coniferous forests of the interior Pacific Northwest. Forest Ecology and Management, 258, 712-721


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

Thin trees within forests: effects on mature trees Forest Conservation

A replicated, controlled study in 2002-2006 in temperate coniferous forest in Washington State, USA (Harrod et al. 2009) found that thinning decreased tree density and basal area and increased their average stem diameter and canopy height. Number of trees/ha (thinned: 205; unthinned: 530) and tree basal area (thinned: 17 m2/ha; unthinned: 34 m2/ha) were lower in thinned than in unthinned plots. In contrast, the average diameter of trees (thinned: 36 cm; unthinned: 30 cm) and height of the base of the canopy (thinned: 9 m; unthinned: 5 m) were higher in thinned plots. Six thinned (retaining 10–14 m2/ha basal area) and six unthinned treatment plots (10 ha) were established in 2002-2003. Data were collected 2-4 years after thinning in six 20 × 50 m plots within each treatment unit.

Use prescribed fire: effects on mature trees Forest Conservation

A replicated, controlled study in 2002-2006 in temperate coniferous forest in Washington State, USA (Harrod et al. 2009) found no effect of prescribed fire on tree density, basal area, average diameter and height. Numbers of trees (burned: 525; unburned: 530/ha), tree basal area (burned: 34; unburned: 34 m2/ha), average diameter (burned: 31; unburned: 30 cm) and height (burned: 6; unburned: 5 m) were similar between treatments. Data were collected in 2006 in six plots (20 × 50 m) within each of six burned (prescribed fire in spring 2004) and six unburned treatment units (10 ha).