Keyword: experiment

• Site-specific relationships of root growth potential to outplanting performance of coastal Douglas-fir (
  http://www.for.gov.bc.ca/hre/pubs/pubs/0010.htm
  Root growth potential (RGP) of a range of Coastal Douglas-fir (pseudotsuga menziesii [Mirb.] Franco) stocktypes and lift dates was examined as a predictor of site-specific outplanting performance under farm-field conditions of three experimentally controlled irrigation regimes. RGP test results were highly variable. The irrigation regimes resulted in site-specific mortality, growth, and form. RGP was weakly related to mortality and growth, but only for the very driest irrigation regime. For predicting survival or growth of Coastal Douglas-fir under different experimental field moisture regimes, the RGP test is of little use. These results raise questions about the use operational utility of RGP where handling, planting, and climate may further confound the relationship between RGP and plantation survival and performance. ...

• The Upper Penticton Creek Watershed Experiment 2002.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0096.htm
  The Upper Penticton Creek Watershed Experiment 2002. ...

• Field studies of seed biology.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0184.htm
  ulture literature are generally not applicable, and traditional ecological studies (e.g., of seed banks) tend to be primarily descriptive with little emphasis on experimental approaches. The primary objective of this manual is to detail methods that have been gleaned from the literature and from personal experience of the authors. It is a manual of methods with some general guidelines and interpretation. Relevant background papers are cited where appropriate, but it is not a literature review. The manual is intended for use by researchers in public and private forest resource management agencies, universities, and colleges. Although specifically directed to tree seed research in forested ecosystems, many of the methods described can be used to study seeds of graminoid, herb, and shrub species in both forest and non-forest plant communities. The extensive background information included in the text also provides valuable reference material for many who have an interest in tree seeds, but who are not dir ...

• Conifer and vegetation response in the BWBSmw 12 years after mechanical and herbicide site preparation.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0229.htm
  ents have intensified the need for long-term information that assesses the effects of brushing activities. Information is required for timber growth-and-yield projections, to assess impacts on non-timber resources and resource user groups, to expand our knowledge of applied forest biology, and ultimately to improve forest management practices. During 1994 and 1995, several vegetation management trials were evaluated ( > 5 years post-treatment) for the possibility of remeasurement to obtain long-term conifer response data. Candidate research trials were screened using published and unpublished reports, experimental design, field surveys, and communications with operational and research staff. Of those candidate trials, the Sunset Prairie and Stewart Lake projects in the Dawson Creek Forest District were chosen for remeasurement. These trials were established by Les Herring (research silviculturist) in 1982–1983. This report summarizes the data collected during November 1995 and August 1996 at the Stewar ...

• Effects of Thinning and Fertilizing Mixed Western Hemlock-Sitka Spruce Stands.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0313.htm
  Limited information exists on the growth and yield of young mixed western hemlock (Tsuga heterophylla) and Sitka spruce (Picea sitchensis) stands on the Queen Charlotte Islands following pre-commercial thinning and fertilization. As a result, research into thinning and fertilization was initiated by the South Moresby Forest Replacement Account research committee. Our research project (Experimental Project [EP] 1097), conducted on Graham Island, investigates tree and stand growth responses to thinning and nitrogen and phosphorus fertilization in young Sitka spruce-western hemlock stands. In this extension note, we describe this project, present the 5-year response results taken from remeasurements after the 1996 growing season, and offer some preliminary conclusions. ...

• The Influence of Initial Espacement on the Growth of a 27-year-old Sitka Spruce Plantation.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0330.htm
  Individual tree and stand characteristics were determined in a 27-year-old plantation of Sitka spruce (Picea sitchensis [Bong.] Carr.) near Terrace, B.C. Planting densities ranged from 478 to 2990 stems per hectare. Three stand components were examined: all stems per hectare, the largest 25% diameter at breast height outside bark (dbhob) stems per hectare, and the largest 250 dbhob stems per hectare. Wider espacements produced trees with larger diameters, crowns, and branches after 27 years. Total volume per hectare was greatest in the closest espacement when all trees were considered, although this relationship reversed when only the largest 250 stems per hectare were examined. The results of this experiment suggest there is considerable flexibility in choosing an optimum stocking level, and a range of 800 to 1400 stems per hectare is recommended. ...

• Modelling snowmelt in a forest and clearcut.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0403.htm
  Daily energy balance and air temperature snowmelt models were evaluated at a high elevation site (Upper Penticton Creek Watershed Experiment) in the southern interior of British Columbia, Canada. Bi-weekly snow water equivalent survey and daily weather data and snow depth were measured in a lodgepole pine forest and large opening. Snowmelt was measured in the opening using snowmelt lysimeters and calculated for the opening and forest from the daily change in snow depth and measured or estimated snow density. The temperature model calibrated with data for 1999 gave reasonable estimates of melt in 2000 and 2001 but tended to overestimate melt early in the season. The energy balance model performed well except for underestimating peak melt rates in the forest near the end of the season. Net radiation provides almost all the energy for melt in the forest and about 70% of the energy in the open. ...

• Introduction to logistic regression models: with worked forestry examples.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0407.htm
  Logistic regression is a useful tool for analyzing data that includes categorical response variables, such as tree survival, presence or absence of a species in quadrats, and presence of disease or damage to seedlings. The models work by fitting the probability of response to the proportions of responses observed. For instance, the number of outplanted seedlings in 50-tree rows that die from frost damage is an observed response. These observed numbers are converted to proportions which are then fitted by models that determine the probability that a seedling will die from frost damage. Normal distribution approximations to the proportions and the consequent analytical methods (e.g., regression and analysis of variance) can be used if large sample sizes exist for each experimental unit. However, logistic regression does not require large sample sizes for the data analysis to be feasible. Furthermore, it is possible to analyze individual tree data. ...

• Replication and Randomized Block Designs.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0408.htm
  In P.G. Comeau and K.D. Thomas (editors). Designing Mixedwood Experiment Workshop Proceedings, March 2, 1995, Delta-Pacific Conference Centre, Richmond, B.C. B.C. Min. For., Res. Br., Victoria, B.C. Work. Pap.20/1996. ...

• The influence of initial espacement on the growth of a 32-year-old white spruce plantation.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0608.htm
  This 32-year-old experimental plantation, near Houston, B.C., is the oldest known espacement (or planting density) study of white spruce (Picea glauca [Moench] Voss) in western Canada. Individual tree and stand characteristics were periodically measured in permanent sample plots for espacements ranging from 420 to 6727 stems per hectare. Pronounced growth differences among espacements were noted after 32 years. Wider espacements produced trees with larger diameters, crowns and branches. Basal area per hectare and total volume per hectare were greatest in the closest espacement. Mean annual increment was estimated at 3.90-4.75 m3/ha per year using the unadjusted Ministry of Forests' yield model for natural stands. TIPSY 2.0 Beta, the Ministry's managed stand yield model, forecast merchantable volume yields of 4.9-6.7 m3/ha per year, depending on espacement. Mean annual increment and rotation age estimates were compared to those in other white spruce studies. Of the four densities tested, ...

• Fertilization date and litter old-growth clipping affects grassland forage production.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0655.htm
  Research Highlights 1989. Kamloops Res. Stn., Prince George Experimental Farm, Kamloops, B.C. pp. 35-41. ...

• Coarse woody debris decomposition documented over 65 years on southern Vancouver Island.
  http://www.for.gov.bc.ca/hre/pubs/pubs/0666.htm
  In 1929-1930, Stig Schenström and J.D. Curtis established an experiment to study thinning dynamics of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) on southern Vancouver Island, British Columbia. As a subcomponent of the experiment, the coarse woody debris (CWD) from the previous stand were mapped and the decay condition classified on five permanent plots. These scaled drawings and classifications were updated in 1945-1947 and 1995-1996. This unique 65-year period of CWD observation confirms that observations of CWD volume loss on Vancouver Island are similar to elsewhere in the Pacific Northwest. The simple exponential decay rate constant was 0.022/year based on volume of primarily Douglas-fir on the five plots. The decay rate constant by large-end diameter was 0.067/year for logs 80 cm. ...

• Measurement and analysis of genetic differences in experimental forest tree (paper birch) populations.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1047.htm
  Measurement and analysis of genetic differences in experimental forest tree (paper birch) populations. ...

• Preliminary assessment of selected communities of soil organisms under different conifer species.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1086.htm
  This study used the second-growth plantations of Douglas-fir, western hemlock, Sitka spruce, and western redcedar of the Ministry of Forests Experimental Project 571 (species-espacement trial established in 1965-1966 on southern Vancouver Island) to take a preliminary look at the effects of different conifer species on collembolan, oribatid mite, and macrofungal species. For all three groups of soil organisms, overall frequency or abundance and diversity were noticeably less under western redcedar compared with the other conifer species. Using similarity indices, we found that the macrofungus communities (species and abundance) differed under the various conifers. The community of forest floor oribatid mites under Douglas-fir was distinct, but we could not detect differences between the other conifer species. We could not detect differences in forest floor collembolan communities between any of the conifers. ...

• Pruning Density and Severity in Coastal Western Hemlock: 4-Year Results.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1110.htm
  Pruning density is the relative number of trees pruned; pruning severity is the amount of live crown removed. Pruning density and severity experiments were installed in two coastal western hemlock (Tsuga heterophylla [Raf.] Sarg.) plantations, 12 and 13 years old, on Vancouver Island. The pruning density experiment indicated that a single 3-m pruning lift significantly reduced 4-year average diameter by 1.3 cm and height by 0.5 m, regardless of whether all or half the trees were pruned on a plot. Treatments in the pruning severity experiments reflected a range of residual crown lengths: 1.5, 2.5, 3.5, and 4.5 m, plus no pruning (control). After 4 years, there were obvious downward trends in both average diameter and height with increasing pruning severity. Significant growth reduction appeared below a threshold of about 50% retained crown ratio. The most severe pruning treatment (1.5 m) reduced 4-year average diameter by 4.3 cm and height by 1.5 m, compared with the control. ...

• Thinning and Pruning Coastal Douglas-fir near Chilliwack, B.C.: 8-year Results.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1111.htm
  In 1991, a thinning and pruning experiment and pruning severity trial were installed in an 11-year-old coastal Douglas-fir (pseudotsuga menziesii [Mirb.] Franco) plantation near Chilliwack, B.C. The thinning and pruning experiment included three levels of thinning (no thinning, thin to 500 stems/ha, and thin to 250 stems/ha) and three levels of pruning (no pruning, prune 250 stems/ha, and prune all stems/ha) arranged in a 3 ×3 incomplete factorial. Eight-year data showed (1) that thinning and pruning effects were independent, and (2) that thinning had no effect on height growth, increased individual tree diameter and volume, but decreased per hectare total stand volume. Pruning to 3 m reduced height and diameter growth in the first 4 years following pruning, but pruned tree growth was equal to that of unpruned trees from 4 to 8 years. An unreplicated pruning severity trial at the same site examined four levels of crown retention (zero, one, two, four whorls remaining). Mortality exceeded 90% on the ...

• Effects of Sitka alder retention and removal on the growth of young lodgepole pine in the central interior of British Columbia (EP 1185): Establishment report.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1168.htm
  A long-term field experiment was established in 1995 in the Stuart Dry Warm Sub-Boreal Spruce (sbsdw3) biogeoclimatic variant in the Vanderhoof Forest District to study the interactions between Sitka alder (Alnus viridis (Chaix) DC. ssp. sinuata (Regel) A.&D. Löve) and lodgepole pine (Pinus contorta Dougl. ex Loud.) in a 1987 cutblock. The main objective of the study was to determine the eVects of diVering levels of Sitka alder retention (0, 500, 1000, and 2000 clumps per hectare) on lodgepole growth after the pine stands were thinned to a uniform density of 1000 stems per hectare. Ancillary studies were planned to measure: (1) the nitrogen fixation rate of Sitka alder, using 15N isotope dilution, (2) the long-term changes in soil nutrient pools, and (3) the decomposition rates and nutrient concentration changes in Sitka alder and lodgepole pine litter. This establishment report details the methods used and documents the initial soil and stand condition at the time of installation of the expe ...

• Effects of Thinning and Fertilizing Mixed Western Hemlock-Sitka Spruce Stands.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1225.htm
  The objective of this thinning and fertilization experiment (Experimental Project [EP] 1097) was to investigate tree and stand growth responses to thinning, and to nitrogen and phosphorus fertilization in a mixed western hemlock-Sitka spruce ecosystem in the Queen Charlotte Islands, British Columbia. The experiment was established before the 1991 growing season. This report presents the 5-year response from remeasurements taken after the 1996 growing season. Two different fertilization levels (no application; application of 250 kgN/ha + 100kgP/ha) and five different thinning levels (no thinning; thin to 1600, 1200, 800, or 400 stems per hectare) were used in an incomplete factorial experiment in a completely randomized block design. Thinning improved diameter growth for hemlock and spruce. Individual tree height was generally not affected by thinning; however, trees in the lowest diameter class grew faster. On average, trees in thinned plots were larger in diameter, slightly taller, and grew faster in ...

• Carnation Creek and Queen Charlotte Islands Fish/Forestry Workshop: Applying 20 Years of Coast Research to Management Solutions.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1230.htm
  Two major studies of fish/forestry interactions have been conducted in coastal British Columbia over the last 25 years. The Carnation Creek Experimental Watershed Program, located on the west coast of Vancouver Island, began in 1970 and is currently the longest-running investigation of the effects of forestry practices on a coastal stream ecosystem in North America. The second initiative, the Fish/Forestry Interaction Program (FFIP) on the Queen Charlotte Islands, began in 1981. About 30 watersheds were included within this program which focused on the effects of landslides on channel morphology and fish habitat, as well as on watershed rehabilitation techniques and silvicultural treatments. Both studies were conducted in similar environments, but each used a different experimental design. The case-study and synoptic approaches have together provided an opportunity to understand ecological responses both over very long time periods and for diverse geographic conditions and logging histories. The purpose of ...

• Mixed mating in an experimental population of western redcedar.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1261.htm
  Mixed mating in an experimental population of western redcedar. ...

• The Upper Penticton Creek Watershed Experiment: A Review at Year 20.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1304.htm
  The Upper Penticton Creek Watershed Experiment: A Review at Year 20. ...

• Silviculture Treatments for Ecosystem Management in the Sayward (STEMS): Establishment Report for STEMS 1, Snowden Demonstration Forest
  http://www.for.gov.bc.ca/hre/pubs/pubs/1336.htm
  Silviculture Treatments for Ecosystem Management in the Sayward (STEMS) is a large-scale, multi-disciplinary experiment that compares forest productivity, economics, and public perception of seven silvicultural regimes replicated at three sites in the Sayward Forest. The STEMS experiment uses silvicultural systems and treatments to create diversity in forest structure that results in a variety of canopy layers (vertical structure) and spatial patchiness (horizontal structure) to enhance biodiversity and wildlife. The STEMS experiment examines seven different treatment regimes, namely: Extended Rotation (non-treatment control) Extended Rotation with Commercial Thinning Uniform Dispersed Retention Aggregate Retention Group Selection Modified Patch Cuts Clearcut with Reserves These silvicultural regimes create a range of gap sizes and frequencies that emulate natural variation in forest structure. STEMS is a replication of the "Silvicultural Options for Harvestin ...

• Snowmelt in a forest and clearcut.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1398.htm
  Methods for obtaining daily snowmelt rates in forest and clearcut environments were evaluated at high elevation sites in the southern interior of British Columbia, Canada (Upper Penticton Creek Watershed Experiment). Snowmelt was measured during spring 1998 to 2002 in a clearcut with snowmelt lysimeters and calculated for the clearcut and a forest from the daily snow pack depth and snow density. Daily melt rate was calculated in the forest and clearcut from weather station data using an air temperature index method and with the energy balance. Measurements were used to calibrate clearcut and forest snow albedo models, to determine solar radiation transmission through the forest canopy and to calculate the canopy view factor for longwave radiation in the forest. Snow temperature measurements were used to define the beginning and end of the melt season when modelling snowmelt. Lysimeter and snow depth and density based measurements of snowmelt agreed quite well. The air temperature index method gave acceptab ...

• An Early History of the Research Branch, British Columbia Ministry of Forests and Range.
  http://www.for.gov.bc.ca/hre/pubs/pubs/1413.htm
  The B.C. Forest Branch (now Service) was created in February 1912 but research activities didn't begin until 1921 when James (Alex) Alexander studied timber utilization, logging slash disposal, natural regeneration, tree growth and yield, and fire protection. In 1923 Assistant Chief Forester Robert St. Clair recommended the establishment of forest experimental stations in the major forest types of the province, resulting in the Aleza Lake Experiment Station near Prince George (in 1924) and the Cowichan Lake Research Station on Vancouver Island (in 1929). The Research Division was formally established in 1927 with a staff of seven and annual expenditures of $34 000. The director was Percy Barr. By 1930 the Research Division of the B.C. Forest Branch was the largest and most active forest research organization in Canada. In the ensuing decades the research program went through many changes and evolved into a province-wide multi-disciplinary organization. Based on archival material and interviews ...