Fodder Biomass Equations Using Individual Tree Distance-independent Models: a Case of <I>Ficus semichordata</I> in Kaski District, Nepal

Abstract

Fodder trees, Ficus semichordata has high feeding value and is regarded as one of the most popular fodder trees for feeding livestock in mid-hills of Nepal. If the amount of fodder biomass yield could be estimated, systematic feeding system could be developed accordingly. Linear regression equations were developed for fodder biomass of F. semichordata tree, expressed as a function of easily measured parameters such as diameter at breast height, crown diameter and tree height. Individual tree distance-independent models were used as most fodder tree species are managed on an individual tree basis. Data were collected from experimental plots established in the farmers' farmland in Kaski district of Nepal. Aspect specific equations were developed at first as the plots were established on four different aspects. The single variable SD<SUB>1.37m</SUB> i.e. stemdiameter at 1.37m height from base best predicted the TFFW i.e. 1.37m 2 2 total fresh fodder biomass (R<SUP>2</SUP> > 0.90, S.E. < 3.30) and EODFW i.e. oven dry fodder biomass (R<SUP>2</SUP> > 0.87, S.E. < 1.42) in all the four aspects. Inclusion of additional variables increased multicollinearity beyond the acceptable range. Inclusion of 2 crown diameter data in the model brought about slight improvement in the performance of the model (R<SUP>2</SUP> > 0.97, S.E. < 2 2 for fresh fodder and R<SUP>2</SUP> > 0.93, S.E. < 1 for oven dry fodder) but the condition index was more than 18 and 20. The data 2 from all the aspects were pooled to develop the single regional model: TFFW = -12.279 + 2.672* SD<SUB>1.37m</SUB> (R<SUP>2</SUP> > 0.91, S.E. < 1.37m 2 3.30), the corresponding model for estimated oven dry fodder weight is EODFW = -3.789 + 0.853* SD<SUB>1.37m</SUB> (R<SUP>2</SUP> > 0.88, S.E. < 1.37m 1.22).