tagged trees in permanent sample plot, Butte, WA

Overview

History

Experimental
Design

Treatment Implementation

Study Areas

Photos of Study Areas

 

  

D E M O
Demonstration of Ecosystem Management Options Study

A Large-Scale Experiment in Structural Retention Harvests in Pacific Northwestern Forests

Study Areas

map of geographic distribution of DEMO blocks Capitol Forest Butte Paradise Hills Little White Salmon Watson Falls Dog Prairie

To establish a broad geographic and ecological base of inference, six blocks were chosen to represent a diversity of forest types in western Oregon and Washington. Blocks encompass markedly different physical environments, mature forest structures, stand ages, and disturbance histories on the Umpqua (Oregon) and Gifford Pinchot (Washington) National Forests, and on the Department of Natural Resources' Capitol State Forest (Table 1). Stands represent the western hemlock, grand fir, white fir, and silver fir zones (defined by the climax tree species). Douglas-fir dominates all sites, but associated tree species vary among blocks.

Click on block locations to view photos of sites

 

 

Table 1. Range of Characteristics of the Six Study Blocks Prior to Harvest

 

Oregon

Washington
 

Watson Falls
(WF)

Dog Prairie (DP)

Butte
(BU)

Little White
Salmon
(LW)

Paradise Hills
(PH)

Capitol Forest (CF)

Elevation (m)

945–1310

1460–1710

975–1280

825–975

850–1035

210–275

Slope (%)

4–7

34–62

40–53

40–66

9–33

28–52

Aspect

flat

SW

E–SE

NW–NE

various

various

Stand age (yr)

110–130

165

70–80

140–170

110–140

65

Tree density (no. / ha)*

310–500

258–475

759–1781

182–335

512–1005

221–562

Tree basal area (m2 ha-1)*

36–52

72–106

48–65

61–77

59–87

54–73

Site index (m)Ά

40–43

30

27–32

30

26–33

37–41

Forest zone

western hemlock

white fir

western hemlock

grand fir

silver fir

western hemlock

Volume CWD (m3 ha-1)

67–191

50–233

91–943

73–289

126–230

131–216
*Trees ³ 5.0 cm dbh.
Ά Height of Douglas-fir at 50 yr.