The effectiveness and potential cost-savings of operator select to manage brush and thin longleaf pine stands

Brett Lawrence , Jeremy Stovall, Matthew McBroom

We present a case study where loggers thinned and managed brush in longleaf pine stands that went unmanaged for a lengthy period in Trinity County, Texas, USA. Stands were overstocked and had a dense, shrubby understory from years of fire exclusion. Our main objectives were to compare the outcomes and cost-savings of loggers selecting trees to thin, or “operator select”, versus timber marking, and whether they were different when attempting to restore longleaf pine stands to an open structure. We also worked closely with loggers to manage brush in place of conventional forestry mulching as a source of additional cost-savings. Twenty-one inventory plots were sampled during prethinning and post-thinning treatment stages, with half marked and the other half left unmarked. The location of unmarked plots was undisclosed to loggers and harvested by operator select methods. We measured no significant difference in forest inventory metrics at marked and unmarked plots following thinning. There was, however, better retention of longleaf pine and removal of loblolly pine in marked areas, and overall precision was higher in marked areas. QMD increased across all plots, woody vegetation decreased significantly, and reestablishment of herbaceous groundcover increased after following thinning with prescribed burning. Using this approach, an estimated $197.53 US per hectare cost for timber marking and $879.34 US per hectare for conventional mulching services was saved. This amounted to an estimated $876.35 US per hectare reduction in project cost to create open longleaf pine structure. When implementing operator select in longleaf pine stands, our results indicate that providing feedback to well qualified loggers can create comparable results to timber marking at a discounted cost, but with small tradeoffs in precision.