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Title: Harvesting small trees for biomass

Journal Article · · Maine Agric. Exp. Stn.; (United States)
OSTI ID:6888242

This study evaluated precommercial, full-tree thinning of saplings and small poletimber (1-8 inches depth breadth and height) using chainsaws and modified farm tractors for skidders. To facilitate cutting large numbers of small trees (1-5 inches), the chainsaw was fitted with a felling frame. The cutter felled and manually bunched up to 145 trees/2.7 tons per productive manhour. Average production, assuming 73% efficiency, was 90 trees/1.8 tons per scheduled hour at a cost of $6.22/ton. Skidding was done by a two-wheel drive grapple skidder and a four-wheel drive farm tractor with double-drum winch. The grapple skidder produced 3.8 tons per scheduled hour at a cost of $8.25 per ton, assuming a 75% utilization rate. The cable skidder produced 4 tons per scheduled hour at a cost of $7.00/ton; preset chokers increased production to 4.7 tons/hour at a cost of $5.96. The key to production was a modified herringbone pattern of corridors which facilitated skidder access to the wood. The weakest link in the operation was the difficult, labor-intensive work of felling and bunching. 14 references.

OSTI ID:
6888242
Journal Information:
Maine Agric. Exp. Stn.; (United States), Vol. 813
Country of Publication:
United States
Language:
English