A TECHNIQUE FOR ESTIMATING BELOW-STUMP BIOMASS OF MATURE LOBLOLLY-PINE PLANTATIONS

A technique was developed for estimating below-stump biomass of mature loblolly pine (Pinus taeda L.). The technique required complete excavation of only three trees and partial excavation (taproot only) of 12 others. A regression methodology for roots >0.6 cm diameter and traditional soil-core sampling for roots <0.6 cm diameter formed the main elements of the technique. Strong relationships were found (1) between biomass of three diameter classes of lateral roots and their proximal end diameter and (2) between diameter at breast height and estimated below-stump biomass for roots >0.6 cm diameter. This technique should be useful for estimating root biomass of plantations of loblolly pine and may be effective for large trees of other species.