Eric Boa wrote: What are the highest yields for plantation species? Figures I've got suggest that eucalypts might, ideally, give up to 20 metric tons per hectare. Someone mentioned poplars giving up to 40 tpa and I'm aware that beyond trees, the grass Miscanthus may outyield these. Eric, Here are some figures for Otago, New Zealand. Latitude 45-46 south (nice cold nights to restrict respiration, but still optimal daytime temps for photosynthesis, and plenty of moisture). Douglas-fir data in a fully stocked stand (1500 stems ha-1), age 45, BA 135 m2 ha-1, TLV 1495 m3 ha-1, MAI 33 m3. This stand is now aged 55 and being felled. I know of other 55 year old stands of Douglas-fir in Dusky Forest further south that had BAs of 160 m2 ha-1, but don't have any production figures other than that. Perhaps the greatest standing volumes for NZ D-fir occur in the high altitude, high BA country around the base of Mt Cook in the south of New Zealand (fully stocked regeneration stands - about 44.5 degrees south) where BA was over 160 m2, and TLV was around the 2000 m3 ha-1 mark. But indeterminate age - p'haps over 70. Radiata in certain sites down south in New Zealand (Tokoiti - where both BA and site index is high) where MAI is 31 m3 on a 28 year old stand NOT fully stocked (around 470 stems ha-1), and yet to peak its MAI. Some higher altitude areas up north may beat this, but very few fully stocked stands exist on high production sites so comparisons are a bit arbitrary. Normally they're felled before they peak. Q. Is this 40 tonnes per ACRE for poplars? Is this for real? I'll pass on the prize, thanks all the same. Chris J K Perley Chris Perley and Associates Forest and Natural Resource Consultants PO Box 7116 Dunedin New Zealand Ph: +64 3 453 4948 Fax: +64 3 453 4945 Mob +64 25 880 977 E-mail: chris@perleyandassoc.co.nz "Think like a mountain." Aldo Leopold
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