A forestry term used to express the productivity of a site in terms of volume growth for Pinus radiata. It is the mean annual volume increment in cubic metres per hectare of a 300 stem per hectare Radiata pine stand at age 30 years.

As a measure of productivity used in modelling and forecasting tree growth and stand yield, it is relevant even where crops are not intended to be thinned to a stocking as low as 300 stems per hectare or grown to age 30.

(This methodology supersedes Site Index (SI), an indication of site productivity based on the expected mean top height of Pinus radiata 20 years from planting.)