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.

Actions

This study is summarised as evidence for the following.

Action Category

Thin trees within forests: effects on mature trees

Action Link
Forest Conservation

Use prescribed fire: effects on mature trees

Action Link
Forest Conservation
  1. Thin trees within forests: effects on mature trees

    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.

  2. Use prescribed fire: effects on mature trees

    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).

     

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust