Timber-grade Studies on Corsican Pine..and their Silvicultural Implications

Authors: R. Fenton
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 1959, Issue N.Z.J.For. 8(2) 1960, pp 218-230, Aug 1960
Publisher: New Zealand Institute of Forestry

Abstract: Logs from a random selection of final-crop 52-year-old Pinus nigra (laricio) Arn. trees were sawn to 1 in. boards and 2 in. framing timber. Grade recovery from sawing to framing was fairly good, but, owing to early encasement of knots, board grades were poor. Maintenance of a deep green crown improves recovery of board grades; acute branch angles and butt sweep accentuate degrade due to knot encasement.
A practical division at a sawmill is to cut logs 8 in. or less in small-end diameter, to boards, and larger logs predominantly to framing timber. Further tending of these old stands is not justified
Investigation of younger stands confirmed that the timing of pruning is vital, and that wider initial spacing up to 8 x 8 ft results in deeper green crowns and gives greater latitude in timing tending.
The maximum-top-height limits deduced for the timing of pruning to 6ft before timber degrade through knot encasement occurs are 14ft for 4x4 ft, 16ft for 6x6 ft, and 20ft for 8x8 ft spacing. Comparable limits for pruning to 16 ft are 32 ft for 4 x 4 ft and 40-44 ft for 8x8 ft spacing.