High Tonnage Harvesting and Skidding for Loblolly Pine Energy Plantations

Abstract

The need for alternative and renewable energy sources is evident in the United States to ensure that the nation’s energy appetite is fulfilled. The southeastern United States has a very promising source for this renewable energy in the form of woody biomass. To meet the energy needs, energy plantations will likely be utilized. These plantations will contain a high density of small stem pine trees. Since the stems are relatively small when compared to current products, the harvesting costs will be increased. The purpose of this research was to evaluate specialized harvesting and skidding equipment that would be able to harvest these small stems cost efficiently. The feller-buncher utilized was a Tigercat 845D with a specialized biomass shear head. The skidder was a Tigercat 630D equipped with an oversized grapple. This equipment was evaluated in a stand with similar characteristics of a southern pine energy plantation. During the study, the feller-buncher achieved an average productivity rate of 52 green tons/PMH and the skidder had an average productivity rate of 123 green tons/PMH. A before tax cash flow model was used to determine a cost per ton for each machine. The feller-buncher costs were $3.48/ton over a 10 year lifespan while the skidder costs were $1.78/ton over the same 10 year life. The results proved that the current system working in a southern pine energy plantation could harvest and skid small stems for approximately $5.26 per ton. After evaluating the operation, several recommendations to benefit the operation were developed. The overall combined cost could be decreased if recommendations for the feller-buncher are successfully implemented.