Table 1. A description of policy changes used to emulate the historical disturbance regime of the Oregon Coast Range. Source: Thompson et al. (2006).


Attribute of the fire regime Method of emulation OFPA† Disturbance-based policy
Severity Legacy structure Five snags or green trees > 28 cm DBH‡ plus 1.5 m3 of downed wood per hectare Interior climate zone: 40% of trees in clumps plus 12 green trees > 60 cm DBH retained per hectare;
Coastal climate zone: 10% of trees in clumps plus 12 green trees > 60 cm DBH retained per hectare
Frequency Annual allowable harvest Five-year wait between adjacent clear-cuts limits harvests indirectly Interior climate zone: 5% of zone harvested each 10-yr period;
Coastal climate zone: 10% of zone harvested each 10-yr period;
OFPA adjacency rules apply
Extent Clear-cut size limit Clear-cut size limit of 48 ha Industrial clear-cut size limit of 250 ha;
Nonindustrial private clear-cut size limit ≤ 48 ha

Oregon Forest Practices Act.
‡Diameter at breast height.