Study evaluates biomass harvesting methods
The U.S. Forest Service Rocky Mountain Research Station has released a set of studies evaluating nearly 40 years of data on the impacts of biomass utilization on soil, tree and plant recovery. The analysis found minimal impact using certain forest harvesting techniques.
Initiated in 1974, the study evaluated the ecological consequences of large-scale biomass harvesting using three different tree removal techniques: group selection, or the removal of small groups of trees; clearcut, or removal of all timber; and shelterwood, or the retention of some trees for shade and structure. All methods were performed using cable logging. On all three sites, the soil was left relatively undisturbed from the harvesting and varying amounts of down wood were left to promote soil organic matter and wildlife habitat. Prescribed fire was applied to some sites to reduce fuels and fire danger. The sites were then tracked over 38 years.
“We did not find any clear evidence that intensive biomass removal negatively impacted these sites, nearly 40 years later these sites were healthy and had minimal observable impact,” said Woongsoon Jang, a research scientist on the study from the University of Montana.