More Floor Less Pulp

Small logs once destined for use in low-value products such as pulp and paper pulp have a new lease on life as flooring thanks to a pilot program in Western Australia. Researchers took logs from six-, eight- and 10-year-old southern blue gum (Eucalyptus globules), a common pulpwood species, and 12-year-old maritime pine (Pinus pinaster) plantation trees and manufactured them into engineered floating floor panels. These plantations have, according to a report from the Rural Industries Research and Development Corp, been on the rise so much that economists are predicting that the number of trees will outpace demand for pulp and paper woodchips, making it necessary to look for alternate markets for the juvenile wood.

Previously, southern blue gum was not considered a good source for sawlogs or flooring because of high growth stresses and a tendency for severe collapse during drying. In response, specific techniques were developed to convert these normally difficult-to-process species into a high-value product. “The drawback to utilizing juvenile hardwoods is the difficulty of avoiding degrading during drying in boards more than 1⁄2 inch thick unless the drying process is very slow,” says Phil Shedley, the project’s principal investigator. “Our work using a super-heated steam process to recover this collapse and return the boards to a flat condition is one of the most significant outcomes of the research,” he adds. The result is a high-quality flooring, with a ‘walnut’ color and numerous feature knots. Other benefits of the flooring are its cost effectiveness and suitability to fluctuating climactic conditions.

This study, funded jointly by the Forest and Wood Product Research and Development Corporation, the Joint Venture Agro-Forestry Program, the Wood and Paper Industries Strategy, Western Australian government instrumentalities and a number of forest products industry participants, demonstrates the value of juvenile wood that was not previously acceptable as a source for flooring, Shedley notes. An added benefit of the study is that it has applications for other hardwood species as well. “The concept and benefits of cutting juvenile logs into lamellae while still green should be applicable to any hardwood species,” he says.

Reprinted from