1. Introduction
In recent years, considerable attention has focused
on the identi®cation and protection of late-successional
forest reserves of the Western US and Canada
(FEMAT, 1993). The reserves are highly valued for
their biological and social values (Swanson and Franklin,
1992).
Protecting the reserves from catastrophic disturbance
requires not only understanding the susceptibility
of the reserve forest, but also the susceptibility
of adjacent stands and the landscape as a whole. Latesuccessional
forests are often predisposed to destructive
crown ®res as a consequence of their multilayered
canopies (Oliver and Larson, 1996). Many
of these reserves are located within a landscape
mosaic of complex ownership and management patterns
in which secondary forests and managed plantations
abut the protected reserves. The risk of ®res in
adjacent stands will depend on their structure, weather
conditions, and ignition sources (Agee, 1993). If a
susceptible structure is relatively common at the landscape-scale,
the risk of a catastrophic ®re affecting the
reserve stand may be large.
Silvicultural treatments such as thinning and prescribed
burning can lessen the ®re-susceptibility of a
given stand (Agee, 1993), however, such intensive