Dear Mr. Benson,
Thank you for your suggestion (and sorry about the delay in replying to you).
As regards the definition of forest used by FAO, SDG and others, no-one claims it is perfect, which is not surprising given the wide variety of circumstances and points of view. However, it has emerged from more than 20 years of discussion and negotiation, and is probably the best possible at present. So everyone should stick with it for the time being.
I am not sure exactly what you mean by “productivity for tree and biomass products”. If you mean net annual increment or another measure of forest productivity in terms of wood growth, I agree this would be desirable – and this measure is often used, for instance in the pan-European indicator set. The problem here is that many countries with a high proportion of natural forests (including Canada) do not measure increment, and could not supply the information. From a (wood-focussed) sustainability point of view, the important thing is that drain (harvests and natural losses) is not higher than increment. At present, it appears not to be possible to measure the different components of this equation for all, or even most, countries. However, the net outcome of this interaction is changes in forest biomass: if drain is higher than increment, growing stock decreases; if not, growing stock is stable or increases. This is covered by indicator 3. So the productivity question is covered indirectly.
Thank you again
Kit Prins
Facilitator
M. Christopher Prins