Article Source : InWood International – Science Report – Issue 54 Page 45 – Dec 2003 (www.inwoodmag.com*)
The forest industry globally is losing critical value at source – cutting trees into logs. And, ironically, the more mechanised an operation, the worse it seems to become.
At a precision forestry symposium in Seattle in June 2003, Professor Glen Murphy from 
Oregon State University showed just how – poorly harvesting processor – heads can perform and that even the Swedes with their uniform spruce forests cannot always get it right. Unbelievable as it may sound on average the value loss of all mechanised log-making operations studied worldwide was a little more than 20%, although the top operators working in more uniform stands lost closer to 10%.
Despite all the efforts to extract maximum value. the so-called `value gap’ is still there, and may even be getting wider as some companies focus once again on productivity and costs.
Manual log making (i.e. people with chainsaws), is actually far more accurate than machines. But it is slower and more dangerous. There is also the added problem that humans, unlike computers, cannot cope with a lot of information – like more than 10 log grades in their head at once. Conversely mechanised log-making operations fail to fully recover value for a number of reasons: some mechanical and the rest operator based.
Mechanised stem processors have replaced people on the ground in forestry operations worldwide, significantly reducing fatality rates. However, processor heads fail to fully deliver on value because they can’t measure sweep or accurately measure length.
Sweep is a problem because it is impossible to determine when a stem is picked up and fed through a processor head. Length measurement is often inaccurate because of slippage of file measuring wheel, usually because branch stubs or nodal swelling cause the wheel to trim more than it should. Despite millions of dollars invested in research, the processor head manufacturers still cannot come up with anything better to measure log length than a wheel.
However, there is something new on the technology front to help close the gap: Logmaister! Not only does it brick stems into logs but it also has the potential to make you bigger bucks!
A product of the engineering skills of Logjiztix / Interpine in Rotorua, it is basically a portable merchandising deck designed to operate in log yards and the forests. The system consists of a merchandised bench and a scanning carriage that can process a 40 m stem in seconds, calculate the optimum cutting pattern, and pass this information on to a processor that cuts the stern into logs and stacks the logs into piles. While basically still a prototype, the Awdon people say they have worked out how to get around the problems that plague processing heads.
For less than NZ$1 million, harvesting operations may finally be able to close the value gap and in the forest (including harvest head).
Article Author : Bill Dyck is a Professional Science and Technology Broker, Based In New Zealand