200
T.T. Veblen and P.B . Alaback
chipping in the 1980s, logging in the Andean forests of the Valdivian
rainforest region involved mainly selective logging of the best-formed
individuals of the most valuable species (especially Nothofagus spp. and
Fitzroya cupressoides). The high-grading of these forests has resulted in
relatively little regeneration of these shade-intolerant species, so that the
timber quality of large areas of native forest in the Valdivian rainforest
region has steadily declined over the past half century. Large areas of
Andean rainforests were logged and burned, and in some cases converted
to cattle pasture. Where regeneration has been protected from livestock,
however, large areas of second-growth Nothofagus-dominated stands have
developed. The patterns of stand development of these Nothofagusdominated second-growth .stands are similar to those of stands which
originate following natural fire, landslides, or floods (Veblen, 1985a).
Much second-growth native forest of substantial timber potential has
been converted to plantations of exotic conifers (especially Pinus radiata
because of the incentives of reforestation legislation (Lara & Veblen,
1992). Today, production of wood chips throughout the Valdivian and
Patagonian rainforest regions is decimating vast areas of native forest.
Large-scale clearcutting comparable in scale to that practiced in the
Pacific Northwest has occurred in some Chilean Fitzroya cupressoides
forests. Following clearcutting in the Andes, the regeneration of F.
cupressoides has been practically nil and sites exploited in the mid-1960s
are dominated by a mixture of shrubs and economically unimportant tree
species (Lara, 1991; Veblen et aI., 1976). Regeneration on logged terrains
in the Coastal Range of Chile, however, is more successful, but a general decline in Fitzroya is still common (Donoso, Sandoval, Grez , &
Rodriguez, 1993; Parker & Donoso, 1993; Veblen & Ashton, 1982). The
greater regeneration success in the Coastal Range following logging may
reflect the presence of some seed trees in contrast to the large clearcuts in
the Andes.
In North America, the deforestation and settlement of the west coast
was one of the most rapid in history, and has contributed to increasing
atmospheric carbon (Harmon, Ferrell, & Franklin , 1990). In the midlatitudes of the Pacific Northwest and northern California most of the
forests in valley bottoms and the most productive sites were cleared
between the mid-1800s and the 1940s. The mid-elevation sites were mostly
cleared during the economic expansion of the 1950's through the late
1960's (Sedell & Duval, 1985). Much of the logging from the 1980s
through the present has been on high elevation sites and less productive
or more remote sites. In British Columbia and Alaska, logging of sea
level sites began on an industrial scale in the 1950s and 1960s, and peaked
in the early 1990s (Sedell & Duval , 1985; V.S .D.A., Forest Service,
unpublished data). Logging harvest volume is expected to decline over
the next four to five decades throughout the Pacific Northwest and north
coast due to overharvesting and a resulting imbalance in forest plantation
T.T. Veblen and P.B . Alaback
chipping in the 1980s, logging in the Andean forests of the Valdivian
rainforest region involved mainly selective logging of the best-formed
individuals of the most valuable species (especially Nothofagus spp. and
Fitzroya cupressoides). The high-grading of these forests has resulted in
relatively little regeneration of these shade-intolerant species, so that the
timber quality of large areas of native forest in the Valdivian rainforest
region has steadily declined over the past half century. Large areas of
Andean rainforests were logged and burned, and in some cases converted
to cattle pasture. Where regeneration has been protected from livestock,
however, large areas of second-growth Nothofagus-dominated stands have
developed. The patterns of stand development of these Nothofagusdominated second-growth .stands are similar to those of stands which
originate following natural fire, landslides, or floods (Veblen, 1985a).
Much second-growth native forest of substantial timber potential has
been converted to plantations of exotic conifers (especially Pinus radiata
because of the incentives of reforestation legislation (Lara & Veblen,
1992). Today, production of wood chips throughout the Valdivian and
Patagonian rainforest regions is decimating vast areas of native forest.
Large-scale clearcutting comparable in scale to that practiced in the
Pacific Northwest has occurred in some Chilean Fitzroya cupressoides
forests. Following clearcutting in the Andes, the regeneration of F.
cupressoides has been practically nil and sites exploited in the mid-1960s
are dominated by a mixture of shrubs and economically unimportant tree
species (Lara, 1991; Veblen et aI., 1976). Regeneration on logged terrains
in the Coastal Range of Chile, however, is more successful, but a general decline in Fitzroya is still common (Donoso, Sandoval, Grez , &
Rodriguez, 1993; Parker & Donoso, 1993; Veblen & Ashton, 1982). The
greater regeneration success in the Coastal Range following logging may
reflect the presence of some seed trees in contrast to the large clearcuts in
the Andes.
In North America, the deforestation and settlement of the west coast
was one of the most rapid in history, and has contributed to increasing
atmospheric carbon (Harmon, Ferrell, & Franklin , 1990). In the midlatitudes of the Pacific Northwest and northern California most of the
forests in valley bottoms and the most productive sites were cleared
between the mid-1800s and the 1940s. The mid-elevation sites were mostly
cleared during the economic expansion of the 1950's through the late
1960's (Sedell & Duval, 1985). Much of the logging from the 1980s
through the present has been on high elevation sites and less productive
or more remote sites. In British Columbia and Alaska, logging of sea
level sites began on an industrial scale in the 1950s and 1960s, and peaked
in the early 1990s (Sedell & Duval , 1985; V.S .D.A., Forest Service,
unpublished data). Logging harvest volume is expected to decline over
the next four to five decades throughout the Pacific Northwest and north
coast due to overharvesting and a resulting imbalance in forest plantation