Forest Investment Account (FIA) - Forest Science Program
FIA Project Y092073

    Natural Regeneration, Mortality and Residual Growth Response 25 Years after Partial Cutting on the Coast
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
An invaluable asset to the province is a continuing source of high quality data on the long-term effect of management treatments and regimes on stand and tree growth and development. The Coastal Stand Management Field Experiments Program, part of the Provincial Growth and Yield (GY) Program, uses statistically sound experimental design and high technical standards for establishing and remeasuring Experimental Projects (EPs). The statistical approach ensures that objective and meaningful conclusions can be drawn from the data collected from experimental plots (EPs). There are a large number of Provincial coastal growth and yield research experiments, and these have been assessed and ranked in terms of their ability to provide quality data. The resulting Coastal GY Field Experiments program consists of only those experiments and installations that can provide high quality data and achieve their treatment response objectives. This proposal is for the remeasurement of at least 131 plots (possibly more if the tendered bids come in lower than expected). The data will be collected according to provincial standards (Forest Productivity Council, 1999) by qualified contractors under an invitation to tender process and the cleaned data loaded into the Research Branch GY relational database for use in the Provincial GY Program. Priority remeasurements this year include:
EP703 Extensive Studies of Fertilizing and Thinning - 64 plots from 7 installation will be remeasured (described above). EP703 was initiated in 1971 to investigate the growth response of Douglas-fir and western hemlock at three levels of fertilization and three levels of thinning in a replicated, factorial design. The experiment originally encompassed 940 permanent plots located at 85 installations throughout coastal BC. Of the original 85 installations, 62 have been highly ranked for importance to the program and most of these high priority installations have had their 8th measurement. In addition to tree diameter, height and condition codes, data has been collected on pre-treatment forest conditions, tree ages, crown width, pathological indicators, site information, soil texture, nutrients and moisture regimes, foliar nitrogen, on-site weather stations, understorey vegetation, mortality and ingrowth. The data from this experiment is the single, largest source of data for coastal stands in BC and has provided the most important validation and calibration data for second-growth coastal hemlock and Douglas-fir. The data has been used by research organizations and consultants in BC, the Pacific northwest, and internationally. It has been used to model the spread and effects of root rot over time, effects of fertilizing and thinning, stand development, crown response and other projects that require long-term tree measurement data.
EP 368 The Adaptability of Certain Tree Species to Different Forest
Experimental Project 368 was established by the B.C. Minsitry of Forests in 1958. It is located about 8 km north of Ucuelet on the west coast of Vancouver Island. The objective of the project was to compare the growth of seven coniferous species: Douglas-fir, grand fir, amabalis fir, Port-Orford cedar, Sitka spruce, western hemlock, and western red cedar, planted on a common site. Each species is planted in 49 tree plots, replicated 7 times. The plots have been measured 7 times and were last remeasured in winter 1998.

EP 554 Correlated Curve Trend Thinning Experiment in Douglas-fir
The CCT methodology was first developed in South Africa by A.J. O’Connor (1935) and is now used throughout the world to evaluate the effects of different spacing and thinning strategies. The classical CCT experiment consists of two series of plots: a “spacing series” and a “thinning series”. Plots in the first series are spaced before the onset of competition and represent a range of final densities. Once the target densities are achieved, the trees are left to grow without further thinning. The second series of plots is used to assess the impact of delayed thinning. These plots are established with various initial densities and are subsequently thinned at different ages and to varying degrees. In this case, thinning generally takes place after the onset of competition. Repeated measurement of the heights and diameters of the trees are made for both series and the resulting growth curves are compared among plots (within and between series) to identify trends attributable to the effects of spacing and thinning. The original 18 plots for E.P. 554 were established in 1959 when the plantation was 14 years old. Plots for the second part of the experiment were set up in 1966. Twelve of the plots (Plots 1, 2, 9-18) are sub-plots of the original plots (the latter have the same numbers as the former). Twenty-eight new plots were added to bring the total to 40 (10 treatments ? 4 blocks ? 1 plot/treatment/block). Trees were measured 9 to 13 times over a period of 41 to 48 years

EP 1121 Effects of coastal hardwoods on mixed stand development. Red alder and bigleaf maple are common components of low elevation CWH zone forests in South-western British Columbia and can have beneficial effects in a forest such as contributing to biodiversity, to long-term site productivity through addition of nitrogen to the soil, to rates of nutrient cycling through influence on characteristics of litter and soil flora and fauna and to ameliorating root disease. Despite the benefits they can be aggressive competitors in conifer stands, and this EP studies the effects of different amounts and spatial arrangements of broadleaves on growth and survival of conifers and broadleaves, stand dynamics and long-term sustainability. This research includes three major components: 1) replacement series field experiments; 2) additive field experiments; 3) "cluster" experiment. Data is used in calibrating and testing mixedwood growth models and provides information on competition thresholds and key processes as a basis for mixedwood management and stand tending decisions in broadleaf-conifer mixtures that must balance timber production, biodiversity, and long-term sustainability. Measurement this year is for one of the replacement series experiments at Holt Creek.
This proposal is also for the analysis and reporting on the 25 year response of growth, regeneration and mortality from intermediate and partial cutting throughout the coast. The analysis proposed here, will provide the first ever look at 25 year dynamics across the range of installations. Although the experiment was meant to examine effects of thinning in pure stands, in fact, the treatments ranged from 20 to 50% basal area removal across mixed species stands varying in age from 15 years to 75 years and can be used to assess response of partial cutting with high retention, especially in situations where extended rotations are desirable.
Related projects:  FSP_Y081073FSP_Y103073

Executive summary (76Kb)

Updated August 16, 2010 

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