A Model to Estimate Noble Fir Bough Weight
Authors: Keith A. Blatner1; Roger D. Fight2; Nan Vance3; Mark Savage4; Roger Chapman5
Source: Western Journal of Applied Forestry, Volume 20, Number 1, January 2005 , pp. 44-49(6)
Abstract:
The harvesting of noble fir (Abies procera) for the production of Christmas wreaths and related products has been a mainstay of the nontimber forest products industry in the Pacific Northwest (PNW) for decades. Although noble fir is the single most important bough product harvested in the PNW, little or no work has been published concerning the estimation of the weight of harvestable boughs from standing trees. The model presented in this article was designed specifically for use in predicting the weight of harvestable boughs from standing trees. A total of 322 noble fir were selected on the west side of the Cascades of Washington and Oregon. The stands and sites for sampling were chosen to represent a wide range of environmental and stand conditions. Sample trees were selected at fixed distances along systematical located lines at each selected site. Circular plots with a 20-ft radius centered at each sample tree were established to provide data on competition. Regression analysis was used to estimate the final model. Variables included in the final model were total tree height, merchantable bough height, dbh2, age at dbh, whorl age for each merchantable whorl, and the associated number of boughs for each whorl as well as the total number of trees within a 20-foot radius of the plot tree. In addition, an intercept shifter (0,1) to designate noble fir stands located north and South of the Marion/Clackamas County line in Oregon (South = 0, North = 1) was included in the model. The overall model was significant at the 0.0001 level with an adjusted R2 of 0.77 West. J. Appl. For. 20(1):44–49.Keywords: Noble fir; boughs; weight; environmental management; forest; forest management; forest resources; forestry; forestry research; forestry science; natural resources; natural resource management
Document Type: Regular article
Affiliations: 1: Department of Natural Resource Sciences Washington State University PO Box 646410 Pullman WA 99164-6410 Phone: (509) 335-6166;, Fax: (509) 335-7862, Email: blatner@wsu.edu 2: PNW Research Station 10600 NE 51st Circle Vancouver WA 98682 3: Forestry Sciences Laboratory 3200 SW Jefferson Way Corvallis OR 973311 4: Washington Department of Natural Resources 1111 Washington St, SE PO Box 47016 Olympia WA 98504-7016 5: Department of Natural Resource Sciences Washington State University PO Box 646410 Pullman WA 99164-6410
