Yield model and yield table construction in Albizia (Albizia lebbeck (L.) under the western agro-climatic zone of Tamil Nadu, Southern India.

The woody legume, Albizia lebbeck, is native to tropical Asia, Africa, and Northern Australia. Owing to its multi-utility, it is widely planted as block plantation and in boundary across community lands. A field study was conducted by measuring the biometric value of trees, viz., height and diameter at every 2-m height using a tree telescope. Besides biometric attributes, age was assessed in order to correlate the age-wise yield. The study was carried out in the western agro-climatic zone of Tamil Nadu in different age classes of trees, viz., 1-5 years, 6-10 years, 11-15 years, 16-20 years, 21-25 years, 26-30 years, and 31-35 years. The uniqueness of the present study is that the yield model construction for Albizia was done for standard stem timber (Volume at diameter 20 cm over bark) and standard stem small wood (Volume between diameter limits of 20 cm and 5 cm both measured over bark). After computing the data and subjecting for multiple linear regression analysis, the model was constructed, so as to develop yield table accurately for Albizia without the help of form factor. The study result developed two exclusive yield models; namely, the standard stem timber yield model for Albizia was Y = (-1.212) + (-0.012*age) + (6.506*diameter) and the standard model for stem small wood was Y = (-0.945) + (-0.045*age) + (2.769*diameter) + (0.262*no. of branches). The prominence of the present study is that yield table computation for Albizia is possible accurately without destructive analysis and the cumbersome process of developing form factor.