The Effect of Ageing on the Mechanical Properties of Eastern White Pine

1976 ◽  
Vol 8 (3) ◽  
pp. 64 ◽  
Author(s):  
G. Attar-Hassan

2019 ◽  
Vol 6 (2) ◽  
Author(s):  
Larissa Bogle-Boesiger ◽  
Todd Davis

The purpose of this project was to research the timber used by Engineers without Borders (EWB) groups in the Joyabaj region of Guatemala. This project aimed to investigate the species of wood, evaluate the quality by assessing the distribution of timber grades, and determine mechanical properties. The results will aid EWB groups in the design of wood structures in the Joyabaj region of Guatemala.Samples were collected for species investigation and mechanical testing. Species investigation was triangulated from interviews with the sawmill owner, construction foreman, testing by the USDA Forest Products Laboratory, and comparisons to literature. The results were inconclusive and indicated multiple species were intermixed at the sawmill with no distinction made when purchased. Timber quality was evaluated by using a visual grading guide developed by the authors to assess the distribution of grades within a large order of lumber. Static bending and compression parallel to grain tests were conducted to obtain modulus of rupture, compression parallel to grain, and modulus of elasticity. Specific gravity was also obtained.The results indicate that three different species were collected. Ninety per cent (90%) of the timber was No. 3 or better and 50% to 80% was No. 2 or better depending on the size. Clear wood testing values were similar to those of Eastern White Pine. Structural design should be performed based on National Design Specification (NDS) design values for a No. 3 or No. 2 Eastern White Pine, depending on the degree of wood selection in the construction process.





2010 ◽  
Vol 40 (3) ◽  
pp. 423-435 ◽  
Author(s):  
Charles R. Drever ◽  
James Snider ◽  
Mark C. Drever

Our objective was to assess the relative rarity and representation within protected areas of Standard Forest Units (SFUs) in northeastern Ontario by applying the concepts of geographic range, habitat specificity, and local population size. SFUs are stand type classifications, routinely employed by forest managers, based on tree composition, disturbance history, and prescribed silvicultural system. We identified several SFUs as rare because of a narrow distribution, association with only one landform type, or lack of at least one stand larger than an ecoregion-specific threshold. In the Boreal forest, rare SFUs comprised stands dominated by eastern hemlock ( Tsuga canadensis (L.) Carrière), red oak ( Quercus rubra L.), yellow birch ( Betula alleghaniensis Britt.), or eastern white-cedar ( Thuja occidentalis L.). Rare SFUs also included eastern white pine ( Pinus strobus L.) and (or) red pine ( Pinus resinosa Ait.) leading stands managed by shelterwood or seed tree silviculture as well as low-lying deciduous stands and selection-managed stands of shade-tolerant species. In the Great Lakes – St. Lawrence forest, rare SFUs were yellow birch stands, stands dominated by conifer species abundant in the Boreal, and shelterwood-managed hardwood stands. Several rare SFUs had <12% of their total area in protection, i.e., stands dominated by eastern white pine, yellow birch, eastern white pine – red oak, or eastern white-cedar. These rare stand types require increased protection in reserves and tailored silvicultural practices to maintain their probability of persistence.



2013 ◽  
Vol 298 ◽  
pp. 71-81 ◽  
Author(s):  
Justin Waskiewicz ◽  
Laura Kenefic ◽  
Aaron Weiskittel ◽  
Robert Seymour


1979 ◽  
Vol 64 (6) ◽  
pp. 924-929 ◽  
Author(s):  
David R. Deyoe ◽  
Gregory N. Brown


Author(s):  
Rebecca L. Stern ◽  
Paul Schaberg ◽  
Shelly A Rayback ◽  
Paula F. Murakami ◽  
Christopher Hansen ◽  
...  

A warming climate and extended growing season may confer competitive advantages to temperate conifers that can photosynthesize across seasons. Whether this potential translates into increased growth is unclear, as is whether pollution could constrain growth. We examined two temperate conifers - eastern white pine (Pinus strobus L.) and eastern hemlock (Tsuga canadensis (L.) Carrière) - and analyzed associations between growth (476 trees in 23 plots) and numerous factors, including climate and pollutant deposition variables. Both species exhibited increasing growth over time and eastern white pine showed greater maximum growth. Higher spring temperatures were associated with greater growth for both species, as were higher autumnal temperatures for eastern hemlock. Negative correlations were observed with previous year (eastern hemlock) and current year (eastern white pine) summer temperatures. Spring and summer moisture availability were positively correlated with growth for eastern white pine throughout its chronology, whereas for hemlock, correlations with moisture shifted from being significant with current year’s growth to previous year’s growth over time. The growth of these temperate conifers might benefit from higher spring (both species) and fall (eastern hemlock) temperatures, though this could be offset by reductions in growth associated with hotter, drier summers.



1959 ◽  
Vol 35 (1) ◽  
pp. 19-21 ◽  
Author(s):  
J. L. Farrar ◽  
W. D. McJannet


1982 ◽  
Vol 12 (4) ◽  
pp. 848-852 ◽  
Author(s):  
D. H. Lambert ◽  
T. C. Weidensaul

Blue spruce (Piceapungens Engelm.), Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco, Noble fir (Abiesprocera Rehd.), and eastern white pine (Pinusstrobus L.) seedlings grown in the greenhouse in peat–vermiculite medium were fertilized with nutrient solutions containing 0.00–0.64 ppm Cu. Maximum growth generally occurred at levels higher than the conventional fertilizer rates of 0.02–0.06 ppm, particularly for Douglas-fir, with subsequent shoot or needle concentrations of 3 or more ppm. Optimum growth of Douglas-fir in a peat–vermiculite medium treated with a single initial drench of 0–100 ppm Cu/L mix occurred over a broad range of foliar Cu concentrations greater than 4 ppm. Supplemental Cu for container-grown conifers thus appears necessary in some cases, but not harmful in others.



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