Predicting branch diameters on second-growth Douglas-fir from tree-level descriptors

1999 ◽  
Vol 29 (12) ◽  
pp. 1829-1840 ◽  
Author(s):  
Douglas A Maguire ◽  
Stuart R Johnston ◽  
James Cahill
Keyword(s):  
Stand Density ◽  
Douglas Fir ◽  
Tree Level ◽  
Basal Diameter ◽  
Tree Diameter ◽  
Crown Length ◽  
Second Growth ◽  
Regression Techniques ◽  
Branch Size

The quality of lumber and veneer recovered from logs of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is directly influenced by the maximum limb size attained on the crop tree. Because limb sizes are influenced by stand-density regimes, a need has arisen for quantitative tools that link a wide array of silvicultural regimes to wood-product quality by accounting for silvicultural effects on crown development. An equation for estimating maximum branch size at a given level within the live crown was developed from data collected on 96 felled sample trees in the Coast Ranges and Cascade foothills of Oregon and Washington. Height and basal diameter of the largest branch within each live whorl were measured on each felled tree, and a predictive equation was developed by various regression techniques. The final mixed-effects nonlinear model estimates maximum branch size as a function of depth into crown and tree diameter at breast height, height, and live crown length.

Load-Carrying Capacity of Second-Growth Douglas-Fir Stump Anchors

1987 ◽  
Vol 2 (3) ◽  
pp. 77-80 ◽  
Author(s):  
Marvin R. Pyles ◽  
Joan Stoupa
Keyword(s):  
Carrying Capacity ◽  
Deformation Behavior ◽  
Ultimate Load ◽  
Douglas Fir ◽  
Load Carrying Capacity ◽  
Test Results ◽  
Tree Diameter ◽  
Second Growth ◽  
Load Carrying ◽  
Load Tests

Abstract In order to quantify the stump anchor capacity of small second-growth Douglas-fir (Pseudotsuga menziesii [Mirb]. Franco) trees, load tests to failure were conducted on 18 stumps from trees 7 to 16.5 in dbh. The tests produced ultimate loads that varied as the square of the tree diameter. However, the ultimate load typically occurred at stump system deformations that were far in excess of that which would be considered failure of a stump anchor. A hyperbolic equation was used to describe the load-deformation behavior of each stump tested and was generalized to describe all the test results. West. J. Appl. For. 2(3):72-80, July 1987.

scholarly journals Shifts in Foliage Biomass and Its Vertical Distribution in Response to Operational Nitrogen Fertilization of Douglas-Fir in Western Oregon

Forests ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 511 ◽  
Author(s):  
Jacob D. Putney ◽  
Douglas A. Maguire
Keyword(s):  
Vertical Distribution ◽  
Nitrogen Fertilization ◽  
N Fertilization ◽  
Douglas Fir ◽  
Tree Level ◽  
Stem Volume ◽  
Parameter Estimates ◽  
Growth Responses ◽  
Basal Diameter ◽  
Dormant Season

Nitrogen (N) fertilization is a commonly applied silvicultural treatment in intensively managed coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) plantations. Field trials were established in a randomized complete block design by Stimson Lumber Company (Gaston, Oregon), to test the economic viability of N fertilization on their ownership and to better understand Douglas-fir growth responses. The 23 stands comprising the trials were Douglas-fir dominated, had a total age of 16–24 years, had been precommercially thinned, and had a density of 386–1021 trees ha−1. Fertilizer was applied aerially at a rate of 224 kg N ha−1 as urea during the 2009–2010 dormant season. In the dormant season of 2016–2017, seven growing seasons following application, 40 trees were felled and measured with the objective of assessing crown attributes and aboveground allometrics. Branch-level foliage mass equations were developed from 267 subsampled branches and were applied to the 40 felled sample trees on which the basal diameter and height of all live branches were measured, allowing estimation of both the total amount of foliage and its vertical distribution. A right-truncated Weibull distribution was fitted to data, with the truncation point specified as the base of live tree crown. The resulting tree-level parameter estimates were modeled as functions of tree-level variables. Stand-level factors not explicitly measured were captured through the use of linear and nonlinear mixed-effects models with random stand effects. Fertilization resulted in more total crown foliage mass in the middle crown-third and caused a downward shift in the vertical distribution of foliage, with implications for feedback responses in crown development and photosynthetic capacity. Defining the morphological responses of Douglas-fir crowns to nitrogen fertilization provides a framework for studying influences on stand dynamics and should ultimately facilitate improved site-specific predictions of stem-volume growth.

scholarly journals Growth of Residual Branches on Pruned Coastal Douglas-Fir

2003 ◽  
Vol 18 (3) ◽  
pp. 185-188 ◽  
Author(s):  
Eric C. Turnblom ◽  
Randol L. Collier
Keyword(s):  
Pseudotsuga Menziesii ◽  
Branch Length ◽  
Douglas Fir ◽  
Anecdotal Evidence ◽  
Modest Increase ◽  
Branch Growth ◽  
Real Risk ◽  
Branch Size

Abstract Anecdotal evidence gathered from pruning crew observations indicates that there may be enhanced branch growth at the new crown base in young pruned coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) trees compared to unpruned trees. This has the potential to reduce the quality and value of the stem above the pruned portion of the bole. An analysis of the size of branches in the remaining crown on pruned trees and matched unpruned trees of the same size at the time of pruning indicates that residual branches do not increase in diameter or length in response to light and moderate pruning. However, with a severe pruning there was a modest increase in branch length. Residual branch size in response to pruning 4 yr after treatment appears to offer no real risk in degrading quality of the unpruned portion of the stem as a cost for increasing the quality of the pruned stem. West. J. Appl. For. 18(3):185–188.

scholarly journals Low Thinning as a Forest Restoration Tool at Redwood National Park

2011 ◽  
Vol 26 (2) ◽  
pp. 91-93 ◽  
Author(s):  
Jason R. Teraoka ◽  
Christopher R. Keyes
Keyword(s):  
Forest Restoration ◽  
Stand Structure ◽  
Basal Area ◽  
Stand Density ◽  
Variable Density ◽  
Douglas Fir ◽  
Redwood National Park ◽  
Second Growth ◽  
Need To Evaluate

Abstract A growing interest in the restoration of young second-growth forests by managers of reserves in the redwood region has led to a need to evaluate restoration-based silvicultural strategies. This case study assessed the effectiveness of low thinning as a forest restoration tool via analysis of stand structure at Redwood National Park's Whiskey Forty Forest Restoration Study. The second-growth stand had more than 5,500 trees ha−1 and 57.0 m2 ha−1 basal area and consisted chiefly of three species: Douglas-fir (the dominant species), redwood, and tanoak. Low thinning reduced stand density but also reduced species richness by eliminating scarce species. Seven years after thinning, growth was enhanced (33.6% gain in basal area), and mortality was minor (3% of all stems); however, Douglas-fir remained competitive in the upper canopy. Its average basal area increment was less than redwood's, but its radial growth was equal and its rate of basal area growth was greater in the years following thinning. We conclude that the thinning improved stand conditions but did not fully satisfy restoration goals and that other thinning methods, such as variable-density thinning, are likely to be more effective at promoting redwood dominance.

Influence of stand density on log quality of lodgepole pine

1988 ◽  
Vol 18 (7) ◽  
pp. 911-916 ◽  
Author(s):  
Louis A. Ballard ◽  
James N. Long
Keyword(s):  
Lodgepole Pine ◽  
Stand Density ◽  
Quality Characteristics ◽  
Exponential Relationship ◽  
Stem Quality ◽  
Rotation Age ◽  
Negative Exponential ◽  
Branch Size ◽  
The Relationship

We examined the relationship between stand density and stem quality characteristics for lodgepole pine (Pinuscontorta). The influence of initial stand density on end of rotation log quality was inferred by analyzing data from unmanaged, rotation-age stands. Quality characteristics examined included first log branch diameters, taper, wood density, and the proportion of sapwood. After differences in diameter at breast height were accounted for, only branch size was strongly influenced by stand density. A strong negative exponential relationship was found between the mean of the five largest branches per first log and number of trees per hectare.

Fungal deterioration of second-growth Douglas-fir logs in coastal British Columbia

1970 ◽  
Vol 48 (9) ◽  
pp. 1541-1551 ◽  
Author(s):  
R. B. Smith ◽  
H. M. Craig ◽  
D. Chu
Keyword(s):  
Seasonal Pattern ◽  
Wood Decay ◽  
Late Summer ◽  
Douglas Fir ◽  
White Rot ◽  
Decay Fungi ◽  
Deterioration Rate ◽  
Second Growth ◽  
Autumn And Winter ◽  
Fungal Deterioration

Fungal deterioration of second-growth Douglas-fir logs, felled each month from August 1961 to May 1962, was studied 2, 4, and 6 years after felling. Decay increased from 10% of log volumes after 2 years to 47% after 6 years. The rate of decay, particularly for the brown cubical type, was greater for autumn- and winter-felled logs than for those felled in the spring and late summer, and closely paralleled the seasonal pattern of ambrosia beetle attack.Decay rates increased with decreasing log size, increasing percentage of sapwood, and increasing height of log above ground. For the same diameter of log, base logs decayed less rapidly than second logs, possibly because of their lower proportion of sapwood in relation to heartwood.Decay expressed as a percentage of total log volume (Y) may be estimated (R2 = 0.71) with the following equation: Y = 13.2 + 10.7X1 − 3.2X2, where X1 = years elapsed and X2 = d.i.b. (diameter inside bark) top of log.Of 30 wood-decay fungi isolated, Naematoloma sp. (N. capnoides or N. fasciculare), which causes a white rot, was associated with the most decay. Fomes pinicola was mainly responsible for brown cubical sap rot, while Poria monticola and P. carbonica caused a brown cubical heart rot at the ends of logs.The significance of variations in deterioration rate and fungal associates is discussed in relation to log durability and salvability.

Evaluating the influence of stem form and damage on individual-tree diameter increment and survival in the Acadian Region: implications for predicting future value of northern commercial hardwood stands

2018 ◽  
Vol 48 (9) ◽  
pp. 1007-1019 ◽  
Author(s):  
Mark Castle ◽  
Aaron Weiskittel ◽  
Robert Wagner ◽  
Mark Ducey ◽  
Jereme Frank ◽  
...  
Keyword(s):  
Growth And Yield ◽  
Tree Level ◽  
Permanent Plots ◽  
Stem Form ◽  
Individual Tree ◽  
Tree Diameter ◽  
Diameter Increment ◽  
Hardwood Species ◽  
Future Value

Northern hardwood species display a variety of forms and defects that can reduce stem quality and complicate their timber management. However, for the most part, growth and yield models do not account for the influence of stem form and damage. This study determined the influence of stem form and damage on growth, survival, and projected future sawlog value among several northern commercial hardwood species. To accomplish this, hardwood trees on 112 permanent plots across three long-term research sites in Maine were assigned stem form and risk classes using a tree classification system developed in New Brunswick. A highly significant influence of stem form and risk on annualized individual-tree diameter increment and survival was found. Inclusion of these equations into a regional growth and yield model highlighted the importance of stem form and defects on long-term simulations as projected stand-level future value was significantly reduced by over 17%, on average (range of 13% to 28%), when compared with projections that did not include that tree-level information. The results highlight the importance of stem form and defects, as well as the need to account for them, in growth and yield applications that assess the forecasted value of commercially important hardwood stands.

scholarly journals Quality of Service as a Predictor of Customer Satisfaction in Healthcare Sector

2020 ◽  
Vol 16 (1) ◽  
pp. 71-87
Author(s):  
Muzna Ashfaq ◽  
Keyword(s):  
Quality Of Service ◽  
Customer Satisfaction ◽  
Pearson Correlation ◽  
Healthcare Services ◽  
Healthcare Sector ◽  
Private Hospitals ◽  
Quality Healthcare ◽  
Effective Strategies ◽  
Regression Techniques

This study examines role of quality of service as a predictor of customer satisfaction in private hospitals. Using a sample of customers of selected private hospitals in Karachi, this study used reliability statistics, Pearson correlation analysis, and OLS regression techniques to analyse the data. The results show that private hospitals are trying to deliver healthcare service that is at par with the expected standards set by their customers. The findings of this study will help management of these hospitals to develop and implement appropriate and effective strategies that would be helpful in delivering quality healthcare services to the patients.

scholarly journals Tree Biomass Equations for Naturally Regenerated Shortleaf Pine

2008 ◽  
Vol 32 (4) ◽  
pp. 163-167 ◽  
Author(s):  
Charles O. Sabatia ◽  
Thomas B. Lynch ◽  
Rodney E. Will
Keyword(s):  
Stand Density ◽  
Seemingly Unrelated Regression ◽  
Tree Level ◽  
Parameter Estimates ◽  
Pinus Echinata ◽  
Shortleaf Pine ◽  
Tree Biomass ◽  
Biomass Component ◽  
Tree Component ◽  
Old Trees

Abstract Aboveground tree-level and branch-level biomass component equations were fitted by nonlinear seemingly unrelated regression, for even-aged naturally regenerated shortleaf pine (Pinus echinata Mill.) in southeastern Oklahoma. Data were obtained from 46- to 53-year-old trees growing in stands that had previously been thinned to densities ranging from 50% of full stocking to overstocked unthinned stands. Stand density affected some of the parameter estimates for trees growing in thinned stands versus unthinned stands. Equations based on dbh alone gave biomass estimates that were not significantly different from those obtained with equations based on dbh, height, and/or crown width. The fitted tree-level biomass component equations were additive in the sense that predictions for biomass components were constrained by the estimation process to sum to total tree biomass. These equations can be used to estimate aboveground tree or tree component biomass for naturally regenerated shortleaf pine in the dbh range of 7–40 cm in southeastern Oklahoma and have potential for application in other shortleaf pine growing areas.

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