Determination of relative economic weights for multitrait selection in coastal Douglas-fir

1998 ◽  
Vol 28 (8) ◽  
pp. 1164-1170 ◽  
Author(s):  
Carol A Aubry ◽  
W T Adams ◽  
Thomas D Fahey
Keyword(s):  
Wood Density ◽  
Wood Quality ◽  
Tree Height ◽  
Douglas Fir ◽  
Stem Volume ◽  
Branch Diameter ◽  
Economic Weights ◽  
Selection Indices ◽  
Multitrait Selection

Relationships between tree traits and tree value for lumber production were investigated. For the purposes of estimating relative economic weights for use in multitrait selection in coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii), tree height, diameter at breast height, and branch diameter were measured on 164 trees (ages 36-66 years). Increment cores from a subsample (92) of these trees were assayed by X-ray densitometry to determine wood density. Bole volume was derived by summing the log volumes of all logs from each tree. Value of lumber recovered from each tree was determined in a separate mill study using both visual and machine stress rated (MSR) grading rules. Multiple linear regression was used to relate tree value to the growth and wood quality traits. Stem volume and branch diameter significantly influenced tree value under visual grading, with relative economic weights of 0.06dm3 and -5.22cm, respectively. Wood density significantly influenced tree value under MSR grading (relative economic weights: 0.06dm3, -6.69cm, and 0.06kg/mdm3, respectively), where lumber strength is measured more accurately. These regression coefficients can be used directly as economic weights in selection indices.

Auswirkungen der Wertastung auf das Douglasien-Wachstum: Ergebnisse aus Nordwestdeutschland

2019 ◽  
Vol 170 (4) ◽  
pp. 207-215
Author(s):  
Andreas Weller
Keyword(s):  
Wood Quality ◽  
Tree Height ◽  
Douglas Fir ◽  
Control Group ◽  
Radial Increment ◽  
Lower Saxony ◽  
Branch Diameter ◽  
Stem Taper ◽  
Positive Effect ◽  
Forest District

Effects of pruning on the growth of Douglas-fir: findings from northwestern Germany Owing to Douglas-firs' insufficient self-pruning ability, for the production of high-grade wood, manual pruning is mandatory. Pruning of live branches increases the branch-free tree volume considerably. Branchiness is important for grading wood quality, but with pruning this detrimental characteristic loses its significance for the value of the Douglas-fir asset. In 1980, trials were conducted in the forest district of Ahlhorn (Lower Saxony, Germany) with three-year-old Douglas- firs to test the effects of live pruning on tree growth. The sample material consists of 93 trees which were periodically pruned beginning from a height of 6 to 8 m up to 20, 40 and 60% of tree height, as well as of 9 Douglas-firs of the unpruned control group. However, only specimens with a pruning height of 60% had live branches removed at each pruning. By means of a multivariate linear regression model the effects of pruning on the dependent variates diameter at breast height (dbh), tree height, stem taper of the butt log and maximum branch diameter approximately at a whorl's height of 5 m were studied up to the age of 39 years. Pruning of live branches had a significant effect on periodic radial growth as well as on bottom log allocation, though not on tree height or branch diameter. Live prune led to moderate reduction of radial increment and had a positive effect on stem taper. The results of the study largely agree with earlier studies on the effects of pruning on Douglas-fir growth.

scholarly journals Evaluation of the provenance plot “Hrubá Skála” (Northern Bohemia) with grand fir at the age of 36 years

2017 ◽  
Vol 63 (No. 2) ◽  
pp. 75-87 ◽  
Author(s):  
Fulín Martin ◽  
Novotný Petr ◽  
Podrázský Vilém ◽  
Beran František ◽  
Dostál Jaroslav ◽  
...  
Keyword(s):  
Czech Republic ◽  
Norway Spruce ◽  
Coastal Region ◽  
Tree Height ◽  
Douglas Fir ◽  
Stem Volume ◽  
Silver Fir ◽  
The Czech Republic ◽  
The North ◽  
Oregon Cascades

The article aims to evaluate the research provenance plot established in 1980 in locality No. 214 – Hrubá Skála (in the north of the Czech Republic), where nine provenances of grand fir (Abies grandis (Douglas ex D. Don) Lindley) provided in the framework of the International Union of Forest Research Organizations project, and one provenance of grand fir, Norway spruce, silver fir and Douglas-fir from a standard commercial source are tested. We present the results of tree height, stem DBH, stem volume production and health status after 36 years. The results correspond with similar experiments in the Czech Republic and abroad and suggest that grand fir provenances from Vancouver Island (British Columbia, Canada) and the Washington (USA) State coastal region show the best production features, while the Oregon Cascades, Idaho and Montana provenances grow more slowly. Comparison with other tree species indicates that the production of grand fir at the investigated age exceeds the production of both Norway spruce and silver fir, and equalizes or gently exceeds even Douglas-fir.

Breeding objectives for pulp production of Eucalyptusglobulus under different industrial cost structures

1993 ◽  
Vol 23 (4) ◽  
pp. 648-656 ◽  
Author(s):  
N.M.G. Borralho ◽  
P.P. Cotterill ◽  
P.J. Kanowski
Keyword(s):  
Wood Density ◽  
Volume Growth ◽  
Cost Savings ◽  
Stem Volume ◽  
Pulp Yield ◽  
Cost Structures ◽  
Selection Indices ◽  
Breeding Objectives ◽  
Forestry Industry ◽  
Pulp Production

Breeding objectives were defined for pulp production of Eucalyptusglobulus Labill, using a simple profit equation relating the monetary cost savings per tonne of pulp produced with stem volume, wood density, and pulp yield. The economic importance of each trait was calculated for five different pulp and forestry industry scenarios with widely different cost structures. Selection indices integrating various combinations of volume growth, wood density, and pulp yield were compared for their ability to meet the different breeding objectives. There was surprising consistency in results across the range of breeding objectives and cost structures studied. It was clear that selection indices integrating volume, wood density, and pulp yield gave the most accurate selection and maximized genetic gain in breeding objectives. The cost savings from indices that included only volume were always much less than one-half, and sometimes as low as one-quarter, as much as those from indices integrating volume and wood traits. In the case study considered, E. globulus in Portugal, these cost savings had substantial implications for company profitability.

Wood Density Determination by X- and Gamma-Ray Tomography

Holzforschung ◽  
2002 ◽  
Vol 56 (5) ◽  
pp. 535-540 ◽  
Author(s):  
A. Macedo ◽  
C. M. P. Vaz ◽  
J. C. D. Pereira ◽  
J. M. Naime ◽  
P. E. Cruvinel ◽  
...  
Keyword(s):  
Bulk Density ◽  
Wood Density ◽  
Wood Species ◽  
Gamma Ray ◽  
Wood Quality ◽  
Density Measurement ◽  
Calibration Procedure ◽  
Density Determination ◽  
Resolution Level

Summary Wood density measurement is related to several factors that influence wood quality. In this paper, a CT image calibration procedure which allows image quantification in terms of dry bulk density is presented for three different X- and gamma-ray energies (28.3, and 59.5, and 662.0 keV). The mass attenuation coefficients measured for a set of eight wood species did not vary significantly, allowing a single calibration for determination of bulk density of air-dried wood samples at each energy. The equation for bulk density calibration obtained was validated using a second set of twelve wood species. Comparison of bulk density determined by CT images, using the calibration procedure proposed, with values obtained by gravimetric methods, presented a very good linear correlation coefficient (R2=0.94). The main advantage of CT imaging over conventional techniques for wood bulk density determination is that it allows detection and quantification of heterogeneities and internal defects. At the sub-millimetric spatial resolution level, it is possible to identify morphological and structural aspects of wood samples.

scholarly journals Predicting Douglas-fir knot size in the stand: a random forest model based on CT and field measurements

2021 ◽  
Author(s):  
Bruna L. Longo ◽  
Franka Brüchert ◽  
Gero Becker ◽  
Udo H. Sauter
Keyword(s):  
Random Forest ◽  
Wood Quality ◽  
Field Measurements ◽  
Detection Algorithm ◽  
Douglas Fir ◽  
Internal Quality ◽  
Internal Diameter ◽  
Branch Diameter ◽  
Standing Trees ◽  
Ct Technology

AbstractBranches are not only of vital importance to tree physiology and growth but are also one of the most influential features in wood quality. To improve the availability of data throughout the forest-to-industry production, information on internal quality (e.g. knots) of both felled and standing trees in the forest would be desirable. This study presents models for predicting the internal knot diameter of Douglas-fir logs based on characteristics measured in the field. The data were composed of 87 trees (aged from 32 to 78 years), collected from six trial sites in southwest Germany, and cut into 4–5 m logs on-site. The internal knot diameter was obtained by applying a knot detection algorithm to the CT images of the logs. Applying the Random Forest (RF) technique, two models were developed: (1) MBD: to predict the branch diameter (BD) at different radial positions within the stem, and (2) MBDmax: to predict the maximum internal branch diameter (BDmax). Both models presented a good performance, predicting BD with an RMSE of 4.26 mm (R2 = 0.84) and BDmax with an RMSE of 5.65 mm (R2 = 0.78). In this context, the innovative combination of CT technology and RF modelling technique showed promising potential to be used in future investigations, as it provided a good performance while being flexible in terms of input data structure and also allowing the inclusion of otherwise underexplored databases. This study showed a possibility to predict the internal diameter of branches from field measurements, introducing an advance towards connecting forest and sawmill.

Late-rotation nitrogen fertilization of Douglas-fir: growth response and fibre properties

2017 ◽  
Vol 47 (1) ◽  
pp. 134-138 ◽  
Author(s):  
Cosmin N. Filipescu ◽  
John A. (Tony) Trofymow ◽  
Ross S. Koppenaal
Keyword(s):  
Nitrogen Fertilization ◽  
Growth Response ◽  
Negative Impact ◽  
Management Practice ◽  
Wood Quality ◽  
Fibre Length ◽  
Douglas Fir ◽  
Stem Volume ◽  
Fibre Properties ◽  
The Impact

Late-rotation fertilization of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) 5 to 10 years before harvesting is a common management practice in British Columbia and the US Pacific Northwest. Despite widespread operational application, knowledge on the impact of late-rotation fertilization on forests, especially fibre properties, is lacking. In this study, we evaluate the growth response and fibre properties following nitrogen fertilization in a productive second-growth coastal Douglas-fir site at age 57 years. Destructive sampling of dominant and co-dominant trees in fertilized and control plots 5 years after fertilization indicated significant gain in stem volume (30%–40%) that was uniformly distributed along the stem. There were no discernible effects on wood quality at the log level in terms of resonance acoustic velocity. However, fibre properties within breast height tree rings indicated significant reductions of ring wood density (by 8%), earlywood density (17%), latewood percentage (10%), and modulus of elasticity (8%). Tracheid dimensions declined in earlywood (reduction of wall thickness by 15%), latewood (radial diameter by 8%), and fibre length (by 6%). Results indicate that late-rotation nitrogen fertilization of Douglas-fir may lead to a significant growth response with only minimal reduction of fibre properties. It is possible that the negative impact on fibre properties could become more significant for repeated applications or higher rates of nitrogen fertilization.

Planting-Site Preparation with Herbicides to Aid Conifer Reforestation

Weed Science ◽  
1983 ◽  
Vol 31 (2) ◽  
pp. 215-221 ◽  
Author(s):  
Edward J. Dimock ◽  
Thomas F. Beebe ◽  
Ernest B. Collard
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Tree Height ◽  
Site Preparation ◽  
Douglas Fir ◽  
Perennial Grasses ◽  
Stem Volume ◽  
Conifer Species ◽  
Volume Yield ◽  
Herbaceous Weed Control

Seven herbicides and two herbicide combinations were applied once either preplant or postplant to control perennial grasses and forbs as planting-site preparation for 2-yr-old seedlings of ponderosa pine (Pinus ponderosaDougl. ex Laws.) and Douglas fir [Pseudotsuga menziesiivar.glauca(Beissn.) Franco] at locations in Washington and Oregon. Hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H, 3H)-dione] applied at 2.2 kg/ha provided most effective and lasting herbaceous weed control in both states. A combination of dalapon (2,2-dichloropropionic acid) and atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] applied at 9.0 + 4.5 kg/ha also proved similarly effective. In Washington, each conifer species responded with exponential growth increases over a 6-yr period. For ponderosa pine and Douglas fir, respectively, hexazinone treatment increased tree height by 58 and 70%, stem diameter by 70 and 69%, and stem-volume yield by 387 and 650% as compared to untreated checks. Corresponding gains for the two conifers associated with dalapon + atrazine were 73 and 54% in height, 63 and 46% in diameter, and 421 and 349% in yield.

Predicting maximum branch diameter from crown dimensions, stand characteristics and tree species

2011 ◽  
Vol 87 (04) ◽  
pp. 542-551 ◽  
Author(s):  
Arthur Groot ◽  
Robert Schneider
Keyword(s):  
Tree Species ◽  
Wood Quality ◽  
Basal Area ◽  
Tree Height ◽  
Remotely Sensed Data ◽  
Individual Tree ◽  
Branch Diameter ◽  
Crown Length ◽  
Stand Basal Area ◽  
Stand Characteristics

Forest resource inventories must include wood quality information to support the optimum use of wood fibre. The objective of this study was to develop models relating maximum live branch diameter (MBD), which affects lumber value, to tree and stand characteristics that can be measured through current and emerging remote sensing technologies. Using non-linear mixed effects models for six Canadian conifer species, as well as for three broad-leaved species, MBD was related to crown radius, tree height, crown length, stand basal area, and basal area of trees larger than the subject tree. Models that included only individual tree characteristics (crown radius, tree height, and crown length) did not perform as well as models that additionally included stand characteristics (stand basal area and basal area of larger trees). Models that took into account tree species performed better than models that did not; in particular, broadleaved species had much thicker branches than conifers. The best model did not show bias with respect to independent variables and had root mean square error of 0.32 cm. For the best model, prediction error was not related to silvicultural treatment. These model characteristics strongly support the potential to successfully predict MBD from remotely sensed data.

Impact of the foliar pathogen Swiss needle cast on wood quality of Douglas-fir

2005 ◽  
Vol 35 (2) ◽  
pp. 331-339 ◽  
Author(s):  
G R Johnson ◽  
Amy T Grotta ◽  
Barbara L Gartner ◽  
Geoff Downes
Keyword(s):  
Moisture Content ◽  
Wood Density ◽  
Wood Quality ◽  
Ring Width ◽  
Wood Properties ◽  
Douglas Fir ◽  
Needle Cast ◽  
Needle Retention ◽  
Foliar Pathogen ◽  
Swiss Needle Cast

Many stands of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) near coastal areas of Oregon and Washington are heavily infected with the foliar pathogen causing Swiss needle cast (SNC) disease, and yet there is very little research on the resulting wood quality. Modulus of elasticity (MOE), modulus of rupture (MOR), microfibril angle (MFA), wood density, latewood proportion, and sapwood moisture content were examined in 20- to 28-year-old trees from 15 stands that were infected with varying intensities of SNC. SNC severity was quantified by measuring needle retention, the number of needle cohorts retained at three crown levels. Correlations between disease severity and wood properties were examined at both the stand and within-stand levels. Trees from heavily infected stands (needle retention <2 years) had higher MOE, wood density, and latewood proportion and lower sapwood moisture content than trees from healthier stands. Breast-height age (BHage) was also correlated with these properties, but age alone did not explain all of the increases. MFA was not associated with SNC severity. Within stands, needle retention was not associated with MOE or MOR. The increase in latewood proportion in diseased stands appears to be the driving factor behind their increase in stiffness (MOE). Ring width decreased with decreased needle retention, and the examined wood properties generally showed stronger correlations with ring width than with needle retention.

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