Figure 7

Relative growth rates of four British Douglas fir ( Pseudotsuga menziesii (Mirb.) Franco) yield tables (Edwards and Christie 1981 ) relating to initial spacing 1.7 m × 1.7 m and crown thinning. A: Relative volume growth. The growth rates were modelled using the Chapman-Richards growth function. B: The standardised relative volume growth rates over volume of the same yield tables based on the same growth model as before.