Tree-choppin’ was once a man’s man’s game, an art so physically demanding that they still hold wood chopping competitions to this day. But no matter how buff and bearded the chopper, there’s no chance of out-logging one of these things. The modern lumberjack is a rugged all-terrain vehicle with a tree harvesting head that hugs a tree trunk like a koala, then executes it with extreme prejudice, strips off bark and branches, and sections it into logs of a pre-determined length in a matter of seconds. It’s mesmerizing to watch, and kind of terrifying, even if you’re not a tree.
Ponsse’s Ergo 8w is an 8-wheeled harbinger of lumber doom. Driven by a 6-cylinder Mercedes engine making 286 horsepower and 1,150 newton-metres of torque, it makes its way over tough and slanted terrain on 26.5-inch tires and carries a crane up to 36 feet long.
At the end of a crane, there’s an ingenious harvester head that grabs a tree trunk very firmly with clamps and rollers. It’s got an inbuilt 60-horsepower chainsaw on a hydraulic arm, capable of felling trees up to 25.6 inches in diameter. Once it’s got a grip, it slices through the trunk like it’s butter.
Having sawed through the trunk, the harvester controls the fall of the tree while maintaining its grip. Then it uses feed rollers to draw the trunk through and saw it into lengths that can be pre-determined from the cabin. As it gets pulled through, up to six de-limbing knives strip the trunk bare.
The sheer speed of this operation is shocking to watch - particularly if you’ve ever done this kind of work by hand. Fifty-foot trees can become piles of neatly cut logs in 20 seconds. The harvesters are relentless and mesmerizing to watch, particularly the way the harvesting head hugs the tree like a friendly teddy bear before murdering and dismembering it.
An in-built software suite logs the ... well, logs as they're cut, communicating wirelessly with the office to make sure the operator gets the desired quantities of timber at the correct lengths, and fleet management tasks are managed through a smartphone/tablet app. Operating a harvester looks like fairly skilled work, so Ponsse also makes simulators for training.
Harvesters like these make logging vastly quicker, more efficient and safer than it once was. And while it’s painful to watch just how quickly they can denude a gorgeous forest landscape, it’s worth remembering how much we still rely on wood as a building material, and that logging can be done sustainably.
Source: Ponsse
