Sustainable Production Forestry THE JOINT FORCES OF CSIRO &
SCION Application of the New Zealand Douglas-fir stand-level growth
model to data from the PNW Leith Knowles and Lars Hansen THE JOINT
FORCES OF CSIRO & SCION NZ stand-level growth model (DF NAT)
Based on data from 1600 permanent plots MTH = fn(SI, age and
latitude) Current annual BA increment = fn(SBAP, age, crown,
competition) Mortality = fn(stocking, DBH) based on Reinekes 3/2
rule BA after thinning: BA2 = BA1*(N2/N1) a THE JOINT FORCES OF
CSIRO & SCION PNW validation data Jim Flewelling facilitated
access to data from the Stand Management Cooperative, University of
Washington 27 silvicultural trials (installations) 303 sample plots
Stands 3-28 yrs of age Roger Fight, US Forest Service, PNW Research
Station also contributed to the study THE JOINT FORCES OF CSIRO
& SCION Fit of PNW data against NZ ht/age curves THE JOINT
FORCES OF CSIRO & SCION Ht/age curves refitted to PNW data THE
JOINT FORCES OF CSIRO & SCION New PNW ht/age curves THE JOINT
FORCES OF CSIRO & SCION Cumulative distribution of Site Index
NZ PNW THE JOINT FORCES OF CSIRO & SCION In PNW, SI increases
with stocking THE JOINT FORCES OF CSIRO & SCION NZ mortality
function slightly underpredicts for PNW THE JOINT FORCES OF CSIRO
& SCION Different definitions for height to crown base PNW:
height above ground to lowest whorl where 3 out of 4 quadrants
contain live branches NZ: the average of height above ground to
lowest live branch, and height above ground to lowest whorl with
majority of branches live THE JOINT FORCES OF CSIRO & SCION
Predicted vs observed crown length for PNW data THE JOINT FORCES OF
CSIRO & SCION Thinning coefficient fitted for each thinning on
each plot BA after thinning: BA2 = BA1*(N2/N1) a PNW first thinning
a = 0.77 PNW second thinning a = 0.82 Average NZ a = 0.71 Average
GB a = 0.66 Average Germany a = 0.83 THE JOINT FORCES OF CSIRO
& SCION SBAP sets BA level THE JOINT FORCES OF CSIRO &
SCION Cumulative distribution of SBAP NZ PNW THE JOINT FORCES OF
CSIRO & SCION SBAP in PNW trials independent of stocking THE
JOINT FORCES OF CSIRO & SCION Site Index and BA potential are
poorly correlated THE JOINT FORCES OF CSIRO & SCION 500-Index
Volume MAI (m 3 /ha/yr) for a stand that has been thinned to waste
to 500 stems/ha by 15m MTH, and grown on to age 40 years Best
growth installation 717: 17.4 m 3 /ha/yr Poorest growth
installation 501: 5.5 m 3 /ha/yr Average for 27 installations: 12.4
m 3 /ha/yr Compares to NZ average of 18.4 m 3 /ha/yr THE JOINT
FORCES OF CSIRO & SCION 500 index for 27 PNW installations THE
JOINT FORCES OF CSIRO & SCION Overall, DF NAT works well
against PNW data THE JOINT FORCES OF CSIRO & SCION Conclusions
SI similar 40 years) SBAP higher in NZ (1.88) vs PNW (1.2)
500-index higher in NZ (18.4) vs PNW (12.4) Slightly higher
mortality in PNW DF NAT needed new height-to-crown-base prediction
function Despite productivity differences (BA not SI), DF NAT works
well in PNW Valuable to repeat the exercise in 5-10 years THE JOINT
FORCES OF CSIRO & SCION Questions and answers
