Tree short-rotation growing

Clearly there are commercial interests in developing clonal lines of trees that have modified or reduced amounts of lignin for fast-growing, short-rotation crops... 

Figure 6.20. Hardwoods are favoured for sawlog production in very short rotation plantations (< 10-15 yrs). The high density in the innermost rings may increase the ability of a tree to absorb energy one might speculate that the first 10-15 yrs for second-growth Canadian softwoods might be compressed into only 1-3 yrs for the fastest growing plantation species. See Yang et al. (1994) Evans et al. (2000) Jozsa and Middleton (1994).

Woody energy crops. Short-rotation woody crops are fast-growing hardwood trees harvested within 5-8 yr after planting. These include hybrid poplar, hybrid willow, silver maple, eastern cottonwood, green ash, black walnut, sweetgum, and sycamore. 

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