Forest Investment Account (FIA) - Forest Science Program
FIA Project Y092258

    Stand Management and Forest Productivity
 
Project lead: de Montigny, Louise (Ministry of Forests and Range)
Author: de Montigny, Louise E.
Subject: Forest Investment Account (FIA), British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Description:
The long-term future of the forest industry on the BC coast depends in part on the productivity of the region's forests and on the choice of silviculturally sound and cost-effective management regimes. Intensive silviculture is considered an important part of the Coast Recovery Strategy. Reliable projections of the results of possible alternative combinations of silvicultural practices are essential for realistic evaluation of forestry investments and for intelligent choices among management regimes. Needed are reliable estimates of response to silvicultural treatments and management regimes, understanding of how product quality and value are influenced by these treatments and regimes, and methods for designing regimes that will produce high yields of wood with desirable properties. The cost of establishing and maintaining a long-term research experiment on the scale necessary to build an adequate regional database to achieve this, are beyond the capabilities of any single organization.
The Stand Management Co-operative (SMC) is a multi-agency growth and yield co-operative established in 1985 formed to create a pool of funding, scientific talent, and long term continuity needed to assess the effects of intensive silviculture. The mission is met through a cooperative effort of land owners, processors, research agencies, and universities. The main objective is to provide a continuing source of consistent, high-quality data on the effects of stand management practices on stand growth and yield, tree growth and yield, wood quality and product recovery through the design, establishment and maintenance of a regional program of integrated research on various aspects of intensive stand management.
Although there have been a considerable number of studies on the effects on initial spacing, pre-commercial thinning and commercial thinning, a number of problems with these studies limit their usefulness (SMC, 1985). These studies generally do not have a wide range of tree spacing, have had density control treatments after prolonged competition and resulting crown reduction, and effects have not been followed over the life of the stand. Measurements are often inconsistent among studies, and there are few sets of comparable data that span a wide range of sites, geographical areas, and density control treatments. Studies have rarely included any examination of the effects of silvicultural treatment regimes on wood properties and value.
Based on these observations, the SMC developed their experimental design to permit effective and operationally practical answers to stand management issues. The basic design considerations were: The data was to be applicable for inferring and predicting treatment response over the entire coastal Douglas-fir region, rather than to an individual location; installations were designed for long-term monitoring over a complete rotation; plot sizes had to be large enough so that over the entire period of observation, the number of trees was sufficient to provide reasonable estimates of diameter distributions, to allow a range of wide range of thinning treatments, and to allow mortality of individual or small groups of trees without greatly influencing plot values; plots were surrounded with adequate size, similarly treated buffers to avoid influence of adjacent stands and treatments; the resulting plot values could be considered a reasonable approximation to results obtainable on an area of operationally treatable sizes.
SMC currently measures and maintains 92 active research installations that are Type 1 (juvenile spacing), II (commercial thinning), or III (espacement) installations and in cooperation with the Northwest Tree Improvement Cooperative, the Type IV (genetic gain by spacing by vegetation control). Each of the SMC installations is a group of permanent sample plots, forming part of the designed experiment, which is established, based on statistical principles to determine and compare the effects of stand management treatments on tree and stand growth and yield. The SMC is currently in the enviable position of having a large high quality database that can effectively answer the questions stated above.

The Ministry of Forests and Range has been a member of the SMC since its inception. Rather than pay membership dues, the Ministry is responsible for the maintenance and remeasurement of the 22 SMC installations located throughout coastal BC. In return, we receive the benefit of SMC staff, student and partner's research projects, data and extension products. The information includes the response of stand to treatments, appropriate treatment levels and timing, impacts of treatment on final yield and impact of damaging agents following treatment. SMC information is made available to B.C. audiences through our partnership with FORREX. In addition, the data for these installations and all other SMC installations contribute to the Provincial Growth and Yield Program (GYP), that provides the data, models, and information needed for essential tasks such as inventory projection, planning silvicultural treatments, calculating stumpage revenues and determining allowable annual cuts.

Of particular relevance to the is the present focus of the Wood Quality Technical Advisory Committee. There are currently 2 studies relating to wood quality. The first, called “Non-destructive evaluation of wood quality in standing Douglas-fir trees and logs” measures the Modulus of Elasticity using standing tree acoustic velocity and milling studies. The objectives for this study are to determine the relationships between the average stiffness of lumber or veneer in a log, stiffness of the log, and stiffness of the parent tree and to what extent are these relationships influenced by stand, tree, log or environmental variables including thinning and fertilizing. The second study is called “Effects of density management and fertilization in SMC Type I installations on breast height branch diameters” attempts to determine if a simple tree measure can be used to estimate the grades of lumber recovery. The objectives of the study are to determine if there is a relationship between the largest limb average diameter (the branch index) and the diameter of the largest branch in the breast height region of the parent tree (the simple tree measure).

New this year is the establishment of a Type V (Douglas-fir Fertilization Study) with objectives to create a tool to predict response of Douglas-fir to N fertilization using site characteristics. The study design has been thoroughly peer reviewed and has been used for several years by Weyerhaeuser for their nutrition studies. The study involves 1 ha areas designated for paired tree fertilization studies used to derive results quickly, effectively and economically. Establishment of 3 of these studies in BC will ensure that the regional potential for response of 15-25 year-old stands to N fertilization within a given vegetation/geology type are evaluated with respect to conditions found in coastal BC. The results of the study will be that forest managers would be able to focus scarce fertilization resources into sites most likely to respond.
Related projects:  FSP_Y081258FSP_Y103258

    Deliverables:
Executive summary (0.2Mb)

Updated August 16, 2010 

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