OFF-ROAD-TRANSPORT:
The concept of off-road-transport has significantly changed over the last 100
years. The addition of the wheeled or tracked machine that could pull or carry
wood caused a revolution in the way forest products were moved out
of the woods. Before the first machines were introduced, trees would be
often hauled from the woods by horse or oxen and delivered to a nearby stream
where the spring flood would wash the logs down stream. Harvesting was very
dependant on having an interconnected system of streams close by as excessive
distances between the cutting area and the stream were costly to cover. The
distances between the cutting area and the stream were increased as machines
that could pull loaded sleds were introduced to the forest. As a result,
places that couldn't be harvested in the past became cost effective. The need
for streams or small river drives decreased as the machines became more
reliable and more powerful. Machines could be used all year round and so the
mill became less and less dependant on the spring flood to ensure its supply
of logs. Bulldozers and big trucks could deliver the logs directly to the
mill. It is in this period that the term off-road-transport (ORT) was likely
first introduced as this became the first period where there was an
on-road-transportation phase.
Currently, ORT is generally accepted to encompass the portion of the
harvesting system that moves trees from the stump area to the collection area
where the main transportation system takes over. It is somtimes difficult to
decide whether a transportation system should be considered as the ORT system
or the main transport system. A good rule of thumb is to consider which
transportation system transports the wood the longest distance. ORT systems
travel much shorter distances than the main transportation system. ORT
systems are relatively easy to distinquish at the present time. They
transport trees/logs from the forest once they have been cut down and deliver
them to the place where transport trucks, ships/barges or trains pick them
up. Since almost all of the main transportation systems in Canada include
either tractor trailers or tri-axled trucks, ORT could be defined as ending
at the landing where the transportation system changes to vehicles travelling
long distances on man made roads.
Off-road-transport is limited to trees being either
dragged or carried by a person, an animal, a machine.
All of the possible alternatives are simply combinations of these or slight
variations. For example, one of the newest ORT methods in use is the
helicopter. It flies over the harvest area and drops a cable with
chokers. Workers on the ground attach
usually one or two logs to the cable and the helicopter flies away and
deposits the logs in a nearby lake or wide river. In the most basic sense,
this is a machine carrying a log. This machine is an example of a
single function machine. It carries out
only one harvesting function.
It is generally accepted that for ORT logs or trees can be;
- Skidding : All or some of the log or tree is dragged on the ground.
- Forwarding : All of the log or tree is carried on a self propelled device.
- Trailoring : All of the log or tree is carried by a device that is not self propelled.
- Cabled : All or part of the log or tree is lifted off of the ground by a cable that is
connected to another cable running on spars in a triangulair shape.
- Flown : All of the log or tree is lifted from off of the ground by either a helium balloon or by a helicopter.
Each ORT method has evolved to suit a particulair purpose. For instance, the
helicopter ORT method becomes costly and not very effective unless atleast one
of three conditions are met. The logs need to big to reduce the amount of
time it takes to choke a load, individual logs must be valuable or the harvest
area must contain conditions that make ORT or on-road-transport by more
conventinal methods too expensive to otherwise harvest.
There is also a possibility that the off-road-transport phase may be combined
with another harvesting phase can also be combined with. These are the
multi-fuction machines. For example there are some machines that severe the
tree from the stump and load the full tree in a bunk on its back
(picture of a KFF). It stops felling trees and
forwards them to the landing when the
bunk becomes full. This particliar machine was called the Koerhing Feller
Forwarder (or KFF) and was used in eastern Canada in the 1980's.
Related Images:
wheeled or tracked machine
forest products
Bulldozers
forwards