COMPARISION FOR THE PHYSICAL AND MECHANICAL PROPERTIES OF SENGON (PARASERIANTHES FALCATARIA (L) NIELSEN) WOOD OF SEED TREES AND OFF-SHOOT TREES

• Main Authors: Marsoem, Sri Nugroho, -, Ari Pujiwinarko
• Format: Article PeerReviewed
• Language: English
• Published: 2005
• Subjects: Forestry Sciences
• Online Access: https://repository.ugm.ac.id/135448/1/Proceeding%20of%20the%20International%20Seminar.pdf; https://repository.ugm.ac.id/135448/
• Institution: Universitas Gadjah Mada

Sengon (Paraserianthes falcataria (L) Nielsen) is known as one of the fast growing tree species. The trees are grown on many forest and particularly community forest in Java Island. One of the efforts to increase the supply of the wood has been done by harvesting the trees in a shorter rotation. Another effort has also been done by growing the trees originated from the shoot (off-shoot trees) instead of those originated from its seeds (seed trees). Visual observation indicates that off-shoot trees show a better growth than those of seed trees, a comparison has therefore been done by studying the physical and mechanical properties of wood from trees of two different regeneration systems. This study has been done by using wood from seed trees (seed-wood) and from off-shoot trees (off-shoot¬wood) of 7 years old of the same site on Wonosobo regency. Wood samples in the free branch stem were divided based on three different radial and axial positions. The wood samples were prepared and measured according to British Standard Methods BS 373. Data obtained from the measurement were analyzed by analysis of variance using a factorial experiment in Completely Randomized Design. The result indicated that although most of the physical and mechanical properties of the wood produced by off-shoot trees were higher than seed trees but the analysis of variance shows that regeneration system only significantly affects green moisture content (GMC) and modulus of elasticity (MOE) of the wood. Interaction between regeneration system and radial position affect air-dry radial shrinkage and total longitudinal shrinkage. Seed trees produced wood of higher GMC (105.48%) than off-shoot trees (76.73%), but having MOE of only 36.57 x 1000 kg/cm2 which is significantly lower than off-shoot trees of 40.34 x 1000 kg/cm2. They show a non significant air dry moisture content (AMC) of 12.77% for seed trees and of 12.83% for off-shoot trees. Both regeneration systems produced rather low average green specific gravity (SG) of only 0.226, and show low and equal average total radial and longitudinal shrinkages of 2.66% and 0.26% respectively, while its average total tangential shrinkage is 4.69% for seed trees and 4.97% for off shoot trees. Both regeneration systems also show low T/R ratio of 1.78 for seed tree and 1.86 for off shoot tree. Sengon trees produced average MOR, compression strength II to grain, and compression strength Y" to grain of 325.68 kg/cm2, 200.84 kg/cm2, and 200.84 kg/cm? respectively.