Pulping of Short Rotation Sycamore Coppice to Maximize Productivity, 2001 Pulping Conference Proceedings

H. Jameel, D. J. Robison, H. -M. Chang, J. McMurray--American sycamore, Platanus occidentalis, is a wide-ranging species across the eastern U.S., typically found in natural stands along stream and river bottoms. The species has long been of interest for plantation forestry, although such systems are poorly developed. Sycamore has great potential for use in short-rotation, high-density fiber/ biomass production systems due to its rapid juvenile growth rate, capacity to tolerate high densities and to coppice after harvest without root sprouting, and its high quality fiber characteristics. In short-rotation (3 to 5 year harvest cycles) high-density (ca. 15,000 stems/ha) systems, the stand is renewed through coppice regrowth (stump sprouting). Such systems maximize the use of site resources, providing productivity 2- to 5-fold greater than traditional plantation systems (1,100 stems/ha, 15 to 25 year harvest intervals). In this research, we examined the pulping and fiber characteristics of young coppice stems (ca. 1 to 9 cm diameter) with bark, as compared to typical larger pulpwood stems (ca. 15 to 25 cm diameter) with and without bark. The pulping of coppice required slightly higher pulping chemicals than the debarked sycamore. The yield was also lower (41% vs 45%). The bleachability of these fiber sources was comparable, but the coppice samples with bark had higher dirt than the debarked sycamore logs. It is estimated that the pulping of coppice represented a penalty of about $15/ODTP. If a coppice source of sycamore fiber could be grown and harvested at a total lower cost than more traditional fiber sources, then there might me some motivation for its cultivation. If the cost of the coppice wood is $5/ODT lower than the sycamore logs, then the cost of pulp production are comparable. If the coppice wood cost is $10/ODT lower than sycamore logs, then the pulp production cost is $10/ODTP less.