Change in aspen density over a range of height ratio classes in the SBPSxc
Mean number of aspen stems
in 2.52m subplot
4.0
3.5
Clusko 2001
No Spacing
3.0
2.5
2.0
1.5
1.0
0.5
0.0
1.00
1.26
- 1.25 - 1.50
1.51- 1.76
2.01 2.26 2.51 2.76 3.01 3.26 3.51 3.76 4.01 4.26 4.51 4.76 5.01 5.26 5.51 5.76
1.75 - 2.00 - 2.25 - 2.50 - 2.75 - 3.00 - 3.25 - 3.50 - 3.75 - 4.00 - 4.25 - 4.50 - 4.75 - 5.00 - 5.25 - 5.50 - 5.75 - 6.00
6.01+
Tall aspen height/target pine height
Mean number of aspen stems
in 2.52m subplot
2.5
Clusko 2008
No Spacing
2.0
1.5
1.0
0.5
0.0
1.00 1.26
- 1.25 - 1.50
1.51- 1.76 2.01 2.26 2.51 2.76 3.01 3.26 3.51 3.76 4.01 4.26 4.51 4.76 5.01 5.26 5.51 5.76 6.01+
1.75 - 2.00 - 2.25 - 2.50 - 2.75 - 3.00 - 3.25 - 3.50 - 3.75 - 4.00 - 4.25 - 4.50 - 4.75 - 5.00 - 5.25 - 5.50 - 5.75 - 6.00
Tall aspen height/target pine height
IDFdk3
The vicious aspen was not as bad as it looked!
6 years old
20 years old ( not brushed)
2
SBSdw1
Pine and aspen: a different story
10 year old pine
3
Recommended changes from research
trial results
Subzone & site
series
AT/PL ht ratio
Density
FG min
pine ht
SBPSxc 01
None
None
1.4
IDFdk3 01
125%
3000
1.4
SBSdw1&2 01
125%
1000
2
Note:
•Only for pine at free growing height
•Only for zonal sites
4
Research suggests that current provincial guidance with
regard to aspen competition in pine stands could use
some tweaking
• Research is only on one site – is this valid?
• We only studied pine and aspen but there are other species out
there
• Results we have developed are for pre-brushing surveys. What
about post-brushing?
• And what about other similar ecosystems?
• What do you mean other values???? Could the changes affect
something else?
5
Verifying the broad application of the results
Why Verify?
• Broad application of research
results from just one site is not
recommended: we collected
information to determine if the research
could be extended across the same unit
• For inclusion of similar
ecosystems: we can’t afford to
complete research in every subzone so we
collected data to determine if we could
extend the research across other
ecosystems
• With operational assistance we sampled a range of
operational sites across a variety of subzones.
6
Other ecosystems in the Cariboo with aspen
communities as defined by the “Expert System”
BEC
Area
ESSFxv1&2
ICHdk
3802
ICHmk3
ICHmw3b
ICHwk2
ICHwk4
IDFdk1b
IDFdk3
IDFdk4
IDFdwa
IDFmw2b
IDFxm
SBPSdc
SBPSmca
SBPSmk
SBPSxc
SBSdw1
Site series
(km2)
425
1123
01
02
03
04
05
06
07
08
09
X
X
AT (L)
X
X
X
X
X
X
AT (L)
X
AT (M)
EP-AT-AC (H)
AT (H)
EP-AT-AC (H)
AT (H)
AT-EP-AC (H)
EP-AC-AT
(H)
X
X
X
AC-EP-AT (H)
AC-EP (H)
AC-EP (H)
EP-AC-AT (H)
X
AT (H)
AT-EP-AC (H)
AT (M/H)
EP-AT-AC (M/H)
32
1726
01a: AT-EP-AC (M)
01b: AT-EP-AC (H)
X
X
EP-AT-AC (L/M)
X
X
AT-EP-AC (H)
X
607
AT-EP-AC (M)
X
X
X
AT-EP-AC (L/M)
X
AT-EP-AC (H)
X
8953
AT (M)
AT (M)
X
AT (M)
X
X
AT (L)
AT (M)
X
3994
AT (M)
AT (L)
X
AT (M)
AT (H)
X
X
AT (M)
AT (M)
2373
01a: AT (M)
01b: AT (M)
X
X
X
X
X
EP (H)
X
X
4227
AT (M)
X
X
X
X
X
X
X
5658
AT (M)
X
AT (M)
X
X
X
X
X
10,898
AT (H)c
X
X
AT (H)
X
AT (H)
AT (M)
EP-AT (M)
AT (M)
X
X
X
X
EP-AT (M)
X
X
X
X
X
X
X
AT-EP (M/H)
AT (M/H)
X
AT (M/H)
EP (H)
AT-EP-AC (H)
EP (M)
X
X
EP (H)
EP (H)
EP-AC (H)
EP-AC (H)
AC (H)
AT-AC-EP
(M)
AT-EP-AC (M/H)
AT (H)
X
X
X
X
X
X
X
X
20
1009
147
1165
3443
SBSdw2
SBSmh
2567
SBSmmb
SBSmwd
87
789
1374
7