| | Unasylva - No. 67 - Timber transportation in the tropics |
 | | Log skidding along bare ground, either full length or with only their butt ends, is much more damaging to the logs as well as to the ground, than log rolling by hand, especially for peeler and veneer logs. |
 | | Logging by manpower ceases in any tropical country as soon as the distance for rolling or skidding of logs becomes too great, and when yarding costs become so high that they cannot be recuperated by the sale price of the timber. |
 | | Logging crawler tractors are at present generally equipped with at least one winch, attached to the rear of the tractor and accommodating up to 110 meters of 1.5- to 2-centimeter hauling cable, depending on its diameter and the tractor size. |
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