From: on behalf of Panel Registry Subject: FW: TNG registration of ...

In sum, the combination of beetle kill and forest fires will be the most significant impact from
climate change to be addressed in the XGCA. The Canadian Forest Service predicts that 80 percent
of the pine will be infected with beetle kill by 2012 (see Box 2). As a result, not only will the forest
fire
hazard increase in terms of frequency, but more intense fires are projected as well (see Box 3).
In
addition,
the main specific impacts on the forest and vegetation will likely be:
• Pine, subalpine fir will no longer be well suited to the XGCA environment
• Aspen presence will likely decline, but will remain on moister slopes and draws
• Douglas‐fir, and many Ponderosa Pine on dry sites,
may be more successful, due to changes
in frost conditions
• There will be more grasslands on marginal sites
• Invasive species, such as knapweed, will increase
• While some culturally important plants will decrease, others might actually increase within
the XGCA, such as the Soopolsllie and Choke Cherry, as areas get drier and warmer.
Interior Douglas­fir (IDF) zone
The IDF zone is characterized by warm dry summers and cool dry winters. It comprises about 22%
of the forested areas of the study area (Figure 2). Two IDF subzones occur in the study area ‐ the
IDFdk4 (dry cool) and IDFdw (dry warm). The IDFdk4 occurs in the Nemiah, Elkin, Taseko River
and Lower Chilko River Valleys. It also occurs as a wide crescent shape band from Cheolquoit Lake
to Tatla Hill within the North Trapline area. The elevation range is from about 950 to 1200m.
Climax stands on zonal (mesic) sites typically have multi‐aged Douglas‐fir canopy with abundant
regeneration. Dominant seral species include lodgepole pine, trembling aspen willow ad rose. Cold
air accumulation areas have lodgepole pine forests similar to those on zonal sites in the Sub Boreal
Pine Spruce xc (very dry cold). Drier sites are dominated by Douglas‐fir, common and Rocky
Mountain
juniper, bluebunch wheatgrass, Rocky Mountain fescue and lichens, while moister sites
have hybrid white spruce, black twinberry, palmate colt’s foot and common horsetail.
The IDFdw subzone occurs at low elevations along the Chilko and Tatlayoko Lakes. Due to the
influence of coastal air masses, the IDFdw has a warmer moister climate relative to most other
parts of the IDF zone in the Cariboo Chilcotin. Climax stands are dominated by multi‐aged Douglas‐
fir and pine grass, with some lodgepole pine and the occasional subalpine fir, while moist areas
have hybrid spruce.
Climate impacts: Climate change will result in hotter and drier summers, warmer winters with
less snow and more rain in the fall and winter in both the IDFdw and IDFdk4. Lower elevations and
southern exposures will experience greater drought stress with associated reductions in tree vigor
and increases in mortality. On northern and moister sites, there will be stands of Douglas‐fir with
scattered
openings from pine and possibly spruce mortality. Fire is a concern in the remaining
lodgepole pine stands in the near term.
These subzones will become much less suited to growing lodgepole pine. Increased drought stress
will lower vigour and increase susceptibility to western gall rust, terminal weevil, dwarf mistletoe
and possibly bark beetles. This increased mortality along with warmer summers will create a high
risk of large intense fires. 54 Lodgepole pine established on cooler aspects will have a better chance
of survival. Douglas‐fir, Ponderosa
pine and spruce should be well adapted up to 2050; however the
KFFS ( 2009) indicates that by 2080,
most of the lodgepole pine regenerated in the early century
54 KFFS 2009.
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