Use shelterwood cutting instead of clearcutting
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Background information and definitions
There are several different shelterwood systems. The basic process is the selective removal of overstorey trees to allow enough light through to the forest floor to create new, even-aged stands below. The remaining mature overstorey trees provide seeds for regeneration and create shelter for the younger trees. Harvesting is done in a series of cuts and may also involve thinning of the lower forest canopies.
Supporting evidence from individual studies
A replicated, site comparison study in 2009 of 21 radio-tracked bats in jarrah Eucalyptus marginata forest in south-western Australia (Webala et al 2010) found that shelterwood harvested forests had more Gould’s long-eared bat Nyctophilus gouldi and southern forest bat Vespadelus regulus roosts than gap release forests. More Gould’s long-eared bat roosts were in remnant trees in shelterwood forests (10 roosts, 37%) than in gap release forests (one roost, 3%). The remainder of tracked Gould’s long-eared bats roosted in mature forest (eight roosts, 30%) and riparian buffers (eight roosts, 30%). Only one southern forest bat roost was found in shelterwoods, and none in gap release forests. Most southern forest bat roosts were in mature unlogged forest (15 roosts, 71%) and riparian buffers (five roosts, 24%). Shelterwood forest had retention levels of 40–60%. Gap release forest had 95% of the mature overstory removed. Riparian buffers and mature forest areas had been undisturbed for >30 years. Eleven Gould’s long-eared bats and 10 southern forest bats were caught with harp traps at two water holes and radio-tracked for 3–8 days in February–March 2009.Study and other actions tested