R Markdown for Aboveground Biomass In this example, we will use linear regression model to predict aboveground biomass using dbh and total tree height. the data is derive from paper which contain, foliage (fol), Branch (bch), stem bark (brk), stem wood (stm), and total aboveground biomass(tab) along with diameter at breast height (dbh), live crown length (lcl), and total tree height (tht).