“…These indicator properties exhibit considerable similarity to the indicators found within the same trial series at age two (Watt et al, 2005). The importance of phosphorus as a determinant of growth in P. radiata has been widely recognised (Grey, 1989), and soil phosphorus is the most commonly used soil chemical property in local and regional models of productivity for this species (Czarnowski et al, 1971;Jackson and Gifford, 1974;Donald, 1977;Hunter and Gibson, 1984;Truman et al, 1983;Grey, 1989;Louw, 1991). In national studies within New Zealand, productivity of mature P. radiata has been predicted previously using both Olsen P (Jackson and Gifford, 1974) and Bray P (Hunter and Gibson, 1984), in combination with other environmental and edaphic properties.…”