• Olalekan Junaid Mississippi State University
  • Frank C Owens Mississippi State University
  • Edward D Entsminger Mississippi State University
  • R. Daniel Seale Mississippi State University
  • Rubin Shmulsky Mississippi State University


southern pine, mechanical properties, modulus of elasticity, modulus of rupture, small clear specimens, lumber, strength, stiffness


This technical note focuses on the modulus of rupture (MOR) and modulus of elasticity (MOE) of small clear southern pine (Pinus spp.) test pieces cut from commercially procured full-size lumber specimens. A production-weighted sample of 476 No.2 grade 2×8s and 2×10s was acquired from retail establishments throughout the southern pine producing region.  The specimens were subjected to static bending tests to measure MOR and MOE.  From 447 of those specimens, a single small clear beam (3.8 × 3.8 × 61 cm) was extracted and subjected to a static bending test of the same properties.  Two-sample t tests showed no evidence of statistical difference in either mean MOE or MOR between the small samples taken from the 2×8s and the 2×10s.  Bivariate correlations and r2 values showed an overall weak relationship (r = 0.30, r2 = 0.09) between the small clears and their parent specimens in respect to MOR.  A more moderate relationship (r = 0.60, r2 = 0.36) was found in respect to MOE between small clears and their parent specimens.  In addition, a relatively strong relationship was found between the MOR and MOE values of the small clears themselves (r = 0.77, r2 = 0.59). It is intended that subsequent publications will examine similar relationships in other grades and sizes.

Author Biographies

Olalekan Junaid, Mississippi State University

Graduate Student

Department of Sustainable Bioproducts

Frank C Owens, Mississippi State University

Assistant Research Professor

Department of Sustainable Bioproducts

Edward D Entsminger, Mississippi State University

Research Associate

Department of Sustainable Bioproducts

R. Daniel Seale, Mississippi State University

Thompson Professor of Wood Science & Technology

Department of Sustainable Bioproducts

Rubin Shmulsky, Mississippi State University

Professor and Department Head

Department of Sustainable Bioproducts


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Technical Notes