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

will be either dead or will struggle under hotter drier conditions. This mortality and past wildfires
may contribute to expanded grasslands. Ponderosa Pine could eventually be the only conifer
adapted to drier sites and Douglas‐fir will be limited to moister areas and require shade for
establishment.
Sub­Boreal Pine­ Spruce (SBPS) zone
The SBPS zone has cold dry winters and cool dry summers due to its location at moderately high
elevations in the rain shadow of the Coast Mountains. The SBPSxc (very dry cold) subzone is the
only subzone of the SBPS in the study area and it comprises also most half of the area (Figure 2). It
occurs on the Chilcotin Plateau between about 1100 and 1500 m. The SBPSxc has the least annual
precipitation of the SBPS subzones and vegetation and soil development has been severely limited
by the cold very dry climate. The landscape is dominated by extensive lodgepole pine forests and
abundant wetlands. On zonal (medium moisture) sites, the forest canopy is often a patchwork of
even‐aged lodgepole pine stands which originated from various fires over time. Scattered aspen
occur on zonal sites and hybrid white spruce occurs on moister sites. Wet meadows are common in
poorly drained depressions. Mountain pine beetle has caused extensive mortality in the pine across
this subzone.
Climate impacts: By 2050 the climate of the SBPSxc will likely be approaching the current climate
of the IDFdw. The risk of wildfires will increase in the short term as more pine is killed by mountain
pine beetle. As the climate warms, lodgepole pine will not be suited to this environment. As pine
declines, it is likely that grassland will expand. Aspen will likely remain in moister areas and
Douglas‐fir
may expand into the area. Since there is more precipitation over all ‐ but warmer, drier
summers,
the wet meadows may contract and expand on a seasonal basis.
Montane Spruce (MS) zone
The MS zone occurs in the transition between the SBPS or the IDF and the Engelmann Spruce
Subalpine fire (ESSF) zone. Lodgepole pine also dominates the MS landscape. There are two MS
subzones in the study area‐ MSxv (very dry very cold) and the MSdc2 (dry cold). The MSxv occurs
in the plateau portion of the study area between 1400 and 1700m. The MSxv is one of the least
productive BEC units in the province for tree growth. Vegetation succession is very slow and pine
stands
greater than 200 years old with only a few spruce or subalpine fir trees in the canopy are
common.
The MSdc2 occurs in the Chilko and Tatlayoko valleys and Stikelan and Cheshi Passes and also
between the IDFdk4 and ESSF in the lower Nemiah Valley. It ranges from 1150‐ 1650m. The climate
is moderated by the costal influences. Zonal stands are dominated by lodgepole pine with moderate
amounts of subalpine fir, aspen, scattered spruce and occasionally Douglas‐fir. Drier sites have
significant amounts of Douglas‐fir and moist sites have hybrid spruce.
Climate impacts: The ClimateBC model projected hotter and drier summers and warmer winters
with slightly less snow in the MSxv subzone. The risk of large wildfires will likely increase due to
warmer temperatures and the increased fuel load from dead lodgepole pine stands. Where it is
found, Douglas‐fir and spruce released by pine mortality will increase in size and vigour over the
near term, but will show signs of moisture stress on all but the wettest of sites. Subalpine fir may
survive in the short term but will have a limited role as a future overstory species. By 2050 there
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