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>Best Douglas-fir stand in the south of NZ - a 60 year old >fully stocked stand with basal area 160 m2/ha and a total >stem volume of 1600 > cubic metres per hectare (merch probably about 1400 cubic metres). And that > ain't a one off - other stands are as good. My carbon figures were > conservative. That is great. So what is holding it up the rest of the plantations in New Zealand? Why not get crackin'and find a way to get them producing 40 cubic meters per hectare per year? There is not a single stand in North America like that. In fact I have never heard of anything like this. Prove it to me by sending the references.... > As to the point about natural forest sometimes being low C relative to the > introduced plantation alternative - we have forest types in NZ that would be > lucky to carry 200 cubic metres live stem volume per ha - simply because the > species are not great big trees. That is pretty tiny in comparison to what we have here. That kind of volume is common on the driest sites here where only lodgepole pine grows and no other species as a result of frequent fire...Douglas-fir would produce more volume but nature is not too friendly to Douglas-fir where there are frequent catastrophic wildfires. What I am saying is that yes you could improve the volume but the stability of the plantation would not be that good in terms of resilience to stressors. I COULD come in and plant some bloody fast > growing trees that would mother the indigenous in terms of C - and according > to your criterion of more total C = better forest, this would be a good > thing. I don't think so. You are putting words into my mouth. I never said what was good nor what was bad. Read my messages. I said that old forests store more Carbon than younger forests. You have reported a stand that is 60 years old that apparently has on it, in hectares, about 40 truck loads of logs. Really....now. I got to see that one day.... So if this stand was left to live for another 100 years there would be well over twice as much volume on it. In fact there would be 2800 cubic meters perhaps by time it became 160 years old. This is assuming of course that growth slows down.... To disprove this would require more than conjecture.... Soon there will be an infestation of Swiss needle cast which will all but wipe out the Douglas-fire monocultures in New Zealand....natural species diverse forests are much more 'resilient' than the the monocrops of Radiata pine any old day...The monospecies forests here are subject to numerous pathogens and don't live very long, well a little longer than grass which is what they resemble. Silviculture grass...... Chao, John _______________________________________________________________________ Free Unlimited Internet Access! Try it now! http://www.zdnet.com/downloads/altavista/index.html _______________________________________________________________________