Then…. ….and Now. Old growth. Second growth. Stand age vs. percent of juvenile wood. When trees grow rapidly so that they are of harvestable size when relatively young, the percentage of juvenile wood increases dramatically (data shown for Loblolly pine). (Zobel & van Buijtenen). influences.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
When trees grow rapidly so that they are of harvestable size when relatively young, the percentage of juvenile wood increases dramatically (data shown for Loblolly pine).
(Zobel & van Buijtenen)
AcceptanceFor End Use
Cost of managementand silviculture
To maximize the value of a plantation over a short rotation.
Value of logs and lumber depend upon:
Logs - large diameters
- long lengths
- clear faces
Lumber - premium lengths and widths
- absence of knots and other defects
Note: Data is not from 2012
Rotation ageForest management/silvicultural options and wood quality
Increased vegetative competition
Trunk with large branches
Maximize piece size
Encourage lower density of mature wood
Lower % of juvenile wood
Maximize stand volume
Fewer and smaller branches
Encourage higher density of mature wood
Higher % of juvenile wood
*Effects of initial spacing distance at time of planting
Loblolly pine plantation – 20% stem removal
Skidder with grapple full of thinnings
Take-out row for skidder access
Schematic sizes and ring width patterns of Douglas-fir logs (sections at 4.5 feet) grown under different regimes (each concentric circle represents six annual rings). Note on a good site, the plantation wood (B) produces wood with large rings at the centre and faster diameter growth than from a natural stand (A). Poor sites will produce narrow rings (C) but still juvenile wood (formed while the cambium is still within the live crown) in both natural stands and plantations. If plantations (B) are not thinned when young, many of them will probably slow down abruptly in growth and appear as D, so that primarily small diameter wood will be available in the future. If they are thinned by removing some of the trees when young (at B), they can produce logs as in E or F, depending on the intensity of the thinning. Future logs such as E or F will be produced primarily if the forest products industry can develop a market for logs such as B, so that such stands can be thinned instead of developing into logs with characteristics such as D. (Oliver)
Maximum knot sizes allowed on the edge and the centre-line of 2x4, 2x8 and 2x12 lumber
Old-growth log quality zones and products value