Sensitivity of acoustic tools to variation in equilibrium moisture content of small clear samples of loblolly pine (Pinus taeda)

2017 ◽  
Vol 15 (1) ◽  
pp. 10-20 ◽  
Author(s):  
Charles Essien ◽  
Brian K. Via ◽  
Thomas Gallagher ◽  
Timothy Mcdonald ◽  
Lori Eckhardt
2003 ◽  
Vol 33 (12) ◽  
pp. 2297-2305 ◽  
Author(s):  
L R Schimleck ◽  
C Mora ◽  
R F Daniels

The application of near infrared (NIR) spectroscopy to the green wood of radial samples (simulated increment cores) and the development of calibrations for the prediction of wood properties are described. Twenty Pinus taeda L. (loblolly pine) radial strips were characterized in terms of air-dry density, microfibril angle (MFA), and stiffness. NIR spectra were obtained in 10-mm steps from the radial longitudinal and transverse faces of each sample and used to develop calibrations for each property. NIR spectra were collected when the wood was green (moisture content ranged from approximately 100% to 154%) and dried to approximately 7% moisture content. Relationships between measured and NIR estimates for green wood were good; coefficients of determination (R2) ranged from 0.79 (MFA) to 0.85 (air-dry density). Differences between calibrations developed using the radial longitudinal and transverse faces were small. Calibrations were tested on an independent set. Predictive errors were relatively large for some green samples and relationships were moderate; R2p ranged from 0.67 (MFA) to 0.81 (stiffness). Dry wood calibrations demonstrated strong predictive relationships with R2p ranging from 0.87 (air-dry density) to 0.95 (stiffness). NIR spectroscopy has the potential to predict the air-dry density, MFA, and stiffness of 10-mm sections of green P. taeda wood samples.


2019 ◽  
Vol 693 (1) ◽  
pp. 7-17
Author(s):  
Krissina Camilla Molinari ◽  
Washington Luiz Esteves Magalhães ◽  
Agnieszka Pawlicka ◽  
Gilmara de Oliveira Machado

2012 ◽  
Vol 42 (3) ◽  
pp. 574-584 ◽  
Author(s):  
Finto Antony ◽  
Laurence R. Schimleck ◽  
Richard F. Daniels

Conventionally, increment cores collected at breast height (1.4 m) have been used to measure wood properties of standing loblolly pine (Pinus taeda L.) trees. This height has been used because of the ease of sampling and cost involved in extracting the cores. In this study, the efficacy of a breast-height core to represent whole-tree specific gravity (SG) and moisture content (MC) was examined. The sampling height that best represents whole-tree SG and MC was identified using the correlation between volume-weighted whole-tree SG and MC with SG and MC measurements collected at different heights within a tree. We found a high correlation between observed whole-disk SG and MC with volume-weighted whole-tree SG and MC at most sampling heights. The strength of the correlation followed a skewed parabolic curve form for both wood properties. The strongest correlations were observed between 4.6 and 6.1 m, with marginally lower correlations at the base of the tree, and the weakest correlations were observed towards the tip of the tree. In addition, it was found that the number of stands and trees that need to be sampled to achieve a certain accuracy in overall mean whole-tree SG and MC was greater if breast height was used as a sampling height compared with the most representative sampling heights identified (4.6 m for SG and 6.1 m for MC).


1990 ◽  
Vol 14 (1) ◽  
pp. 48-51 ◽  
Author(s):  
J. B. Jett ◽  
L. John Frampton

Abstract At moisture contents of less than 15%, loblolly pine (Pinus taeda L.) pollen displayed a marked sensitivity to rehydration prior to in vitro germination testing. At moisture contents above 15%, percent germination was relatively insensitive to increasing moisture content. The relationshipbetween length of rehydration time and pollen moisture content was highly significant. However, the commonly used 16-hour rehydration period is longer than is necessary since 1-2 hours of rehydration adequately ensure peak germination. Shortening of the rehydration period allows operationaltree improvement programs to test a greater number of pollen lots in a given period of time. South. J. App. For. 14(1):48-51.


2016 ◽  
Vol 74 (6) ◽  
pp. 857-866 ◽  
Author(s):  
O. Oyedeji ◽  
O. Fasina ◽  
S. Adhikari ◽  
T. McDonald ◽  
S. Taylor

2006 ◽  
Vol 54 (4) ◽  
pp. 425-430
Author(s):  
T. Árendás ◽  
L. C. Marton ◽  
P. Bónis ◽  
Z. Berzsenyi

The effect of varying weather conditions on the moisture content of the maize grain yield was investigated in Martonvásár, Hungary from late August to late September, and from the 3rd third of September to the 1st third of Novemberbetween 1999 and 2002. In every year a close positive correlation (P=0.1%) could be observed between the moisture content in late September and the rate of drying down in October. Linear regression was used each year to determine the equilibrium moisture content, to which the moisture content of kernels returned if they contained less than this quantity of water in late September and harvesting was delayed. In the experimental years this value ranged from 15.24-19.01%.


Genetics ◽  
1999 ◽  
Vol 151 (1) ◽  
pp. 321-330 ◽  
Author(s):  
Mitchell M Sewell ◽  
Bradley K Sherman ◽  
David B Neale

Abstract A consensus map for loblolly pine (Pinus taeda L.) was constructed from the integration of linkage data from two unrelated three-generation outbred pedigrees. The progeny segregation data from restriction fragment length polymorphism, random amplified polymorphic DNA, and isozyme genetic markers from each pedigree were recoded to reflect the two independent populations of parental meioses, and genetic maps were constructed to represent each parent. The rate of meiotic recombination was significantly greater for males than females, as was the average estimate of genome length for males {1983.7 cM [Kosambi mapping function (K)]} and females [1339.5 cM(K)]. The integration of individual maps allows for the synthesis of genetic information from independent sources onto a single consensus map and facilitates the consolidation of linkage groups to represent the chromosomes (n = 12) of loblolly pine. The resulting consensus map consists of 357 unique molecular markers and covers ∼1300 cM(K).


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