scholarly journals Fibril angle of loblolly pine wood as related to specific gravity, growth rate, and distance from pith

1973 ◽  
Vol 7 (4) ◽  
pp. 251-255 ◽  
Author(s):  
Charles W. McMillin
1986 ◽  
Vol 64 (5) ◽  
pp. 1046-1049 ◽  
Author(s):  
J. D. DeAngelis ◽  
T. E. Nebeker ◽  
J. D. Hodges

Formation of radial resin ducts and their associated secretory cells in loblolly pine (Pinus taeda L.) is influenced by the age and growth rate of the annual ring in which the ducts are formed. The spatial pattern of radial ducts on the tangential plane is nonrandom, exhibiting a regular or dispersed pattern. A significantly higher density of radial ducts was found in the inner, first-formed growth rings at all heights within the tree. Radial duct formation was found to be positively correlated with radial growth rate, when growth rate is expressed as increment of cross-sectional area growth. These findings may partially explain why older, slower growing trees tend to be more susceptible to attack by the southern pine beetle, Dendroctonus frontalis Zimmermann, and associated microorganisms, since the resin-producing system is a primary defense against these agents.


2014 ◽  
Vol 127 ◽  
pp. 117-123 ◽  
Author(s):  
G. Hehar ◽  
O. Fasina ◽  
S. Adhikari ◽  
J. Fulton

1982 ◽  
Vol 6 (3) ◽  
pp. 177-180
Author(s):  
J. B. Jett ◽  
J. T. Talbert

Abstract Data from thinnings of 11 genetic tests with an average age of 10 years and from 364 eight-year-old second-generation selections were analyzed to provide an estimate of gain from one cycle of selection for wood specific gravity. Utilizing mid-parent, mature, wood specific gravities and progeny juvenile wood specific gravities, coefficients of genetic prediction, CGP = 0.55 and 0.41, were calculated for the genetic test thinning sample and second-generation selection sample. Expressed as a percentage of the mean, gain from selection was calculated to be 2.6 percent. A strategy was also developed to include wood specific gravity in the North Carolina State Cooperative's second-generation loblolly pine (Pinus taeda L.) improvement program. High heritability figures indicate little need to develop extensive family information for wood specific gravity in advanced-generation breeding programs.


2009 ◽  
Vol 39 (5) ◽  
pp. 928-935 ◽  
Author(s):  
Finto Antony ◽  
Lewis Jordan ◽  
Richard F. Daniels ◽  
Laurence R. Schimleck ◽  
Alexander Clark ◽  
...  

Wood properties and growth were measured on breast-height cores and on disks collected at different heights from a thinned and fertilized midrotation loblolly pine ( Pinus taeda L.) plantation in the lower Coastal Plain of North Carolina. The study was laid out in a randomized complete-block design receiving four levels of nitrogen (N) fertilizer: unfertilized control and 112, 224, and 336 kg/ha plus 28 kg/ha of phosphorus with each treatment. The effect of fertilization was analyzed for the whole-disk and for a 4 year average following fertilization on data collected from breast-height cores and from disks. The fertilization treatments did not significantly affect whole-disk wood properties but significantly increased radial growth. Fertilization rate of 336 kg/ha N significantly reduced 4 year average ring specific gravity and latewood specific gravity. Wood properties of trees that received 112 and 224 kg/ha N were not affected following treatment. There was no height related trend in wood property changes due to fertilization. Fertilization significantly increased ring basal area and earlywood basal area. In summary, there was a decline in wood properties and an increase in basal area growth immediately after fertilization; both depended on the rate of fertilizer applied irrespective of height.


1989 ◽  
Vol 67 (12) ◽  
pp. 3498-3505 ◽  
Author(s):  
David S. Goldhammer ◽  
Frederick M. Stephen ◽  
Timothy D. Paine

Two symbiotic fungi (SJB 122, an unidentified basidiomycete, and Ceratocystis minor (Hedgecock) Hunt variety barrasii Taylor) and one pathogenic phoretic fungus (C. minor (Hedgecock) Hunt variety minor) of the southern pine beetle, Dendroctonus frontalis Zimmermann, were inoculated onto six different concentrations of D. frontalis frass, loblolly pine (Pinus taeda L.) phloem, and uric acid media to observe radial growth rates and chlamydospore production. The average radial growth rate per day of C. minor var. barrasii increased significantly from the control on all three media, but growth was faster at increased concentrations of added phloem compared with the other supplemented media. Significant increases in chlamydospores produced by C. minor var. barrasii from the control occurred only on frass media, with more chlamydospores being produced at higher concentrations. The average radial growth rate per day of SJB 122 fungus increased significantly from the control on only one concentration of phloem and two concentrations of uric acid, but decreased significantly on low concentrations of frass media. SJB 122 chlamydospore production increased with increasing concentration on frass, was not different from the control on phloem, and increased significantly at intermediate concentrations on uric acid. Ceratocystis minor var. minor average radial growth rate per day increased with increasing concentration on both frass and phloem media but on uric acid decreased significantly at higher concentrations, following an initial signficant increase as compared with the controls.


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