| Summary: | Trees containing large growth stresses, leads to significant losses due to split, checked and also warped. The variation of growth-stress in teak trees grown in the three community forest sites of Gunungkidul regency was observed. The released strain levels were also discussed in relation to the growth-rate and specific gravity. The strains released in the longitudinal and tangential directions were measured by the strain-gauge method. The values of longitudinal released strain at the periphery of the stem were ranged from -130,5 to -999,5 µє whereas tangential released strain were from -103 to 1411,5 µє. Some high values of longitudinal released strain indicated the presence of tension wood. Further, intra-tree variation of growth stress showed no particular tendencies among the samples. There were significant differences in the longitudinal strain as samples from Nglipar site showed the highest amounts (-628,25 ± -223,73 µє). However, no significant correlation was found between the values of released strains with the growth-rate and specific gravity. The radial distributions of internal residual-stress were varied among the individuals which some trees exhibited steeper released strain gradients. Thus, it is important to reduce the gradient from pith to periphery of released-strain patterns to prevent the defect related to the growth stresses.
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