We evaluated three different species: radiata pine, Douglas fir and
Eucalyptus nitens. For radiata pine we assumed an average New
Zealand ex-farm site of site index4 30.2 mand 300 Index5 of 29m3/ha/
year. We evaluated three different silvicultural regimes:
• Clearwood (plant 800 stems/ha, prune to 5.5 m in 2 lifts, thin to
250 stems/ha at age 8 years).
• Framing (plant 800 stems/ha, thin to 375 stems/ha at age 8 years).
• No thin (plant 800 stems/ha, no thinning).
The Douglas fir site is an average New Zealand site with a site
index6 of 31.3 mand a 500 Index7 of 18.4m3/ha/year. The silvicultural
regime is plant 1650 stems/ha, thin to 500 stems/ha at age 15 years.
The Eucalyptus nitens site has site index8 25.6 m. The silvicultural
regime is plant 900 stems/ha with no thinning.
We estimated log and carbon yields using the Radiata Pine and
Douglas fir Calculators (NZTG 2003) and, in the case of Eucalyptus
nitens, the Forest Carbon Predictor implementation of C_Change
(Beets et al. 1999).
Financial criteria used are Land Expectation Value (LEV) and Net
Present Value (NPV) at an 8% real discount rate9 (Manley 2007).
Current log prices were used — in the case of radiata pine published
MAF10 12-quarter average prices. Industry average costs were used. A
range of carbon prices was used with $30/t CO2 as a base case — 2008
prices for secondary Certified Emission Reduction (CER) units were
around this level.11 A fixed cost ($60/ha/year) was assumed for the
costs of measurement, auditing, registration associated with carbon
trading. For the estate-level analysis it was assumed (based on
information from forest managers) that new land for afforestation