Paper & Cardboard

“Thinning” takes place where alternating rows or the weakest trees are removed to give the remaining trees room to expand and continue to grow at the maximum efficiency. The trees removed at these early stages are often debarked, chipped and used as pulp because they are too small for timber. Thinning may be repeated several times depending on the type of tree and row spacing. In a Pine forest around two thirds of the saplings originally planted are thinned out before the forest has reached maturity.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The trees are usually also pruned, this is when branches or stems are removed. Pruning is done from the ground up to around 4 metres after 5 years and up to 6.5 meters after 7 years. This is usually to produce more valuable knot free timber in the long run. The plantation eventually becomes mature and its growth rate slows, it is not economically viable to grow the trees larger and the plantation is ready for harvest. For Pine, maturity is reached in 25 - 35 years with around 300 trunks per hectare after final thinning.

 

 

 

Harvest, Felling and Transport

Logging begins with felling the trees usually using a chainsaw.  Forestry workers cut the branches off the tree and cut it into logs ready to be moved to a landing area. A Skidder is then used to drag the logs to a landing area where they are milled or loaded onto a truck to be taken to a saw mill.

 

A modern skidder is usually a diesel four wheel drive tractor that attaches to logs with either a cable or a grapple. Grapple skidders have a boom and a hydraulic grapple which clamps onto the logs and allows them to be dragged around. Cable skidders reel out and hook on to a load of logs which is then winched back towards the skidder, this is suitable for steeper terrain than a grapple skidder as the heavy machine does not have to get right close to the felled logs, they can be winched onto flatter terrain and dragged to the landing site. However a grapple skidder is much more labour intensive to use as it requires the operator to unreel a heavy steel cable and hook on to logs.

Historically horses or powered winches has been used to move the logs.

 

In larger forests, requiring greater efficiency a heavy vehicle called a forestry harvester might be used, this fells the trees, debranches the trunks, and cuts the logs into predefined lengths accurately. A forestry harvester can load the cut logs easily into a pile for skidding or onto a forwarder which carries the logs rather than drags them, reducing environmental impact.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Logs to Paper

The logs are loaded onto a truck with a digger and carted to a saw mill.

To make paper the wood needs to first have the bark removed in a cylinder known as a debarking drum as this cannot be used for paper and so is used for fuel and mulch. The wood then needs to be chipped which reduces it to small squares.  

 

Logs are usually not chipped straight from the forest in a pulp mill unless they are of lower quality wood or are too small to be made into timber. Most logs go to a saw mill and are cut into boards and planks and used for housing and construction projects. The resulting woodchips from the various saws, edgers and trimmers within a saw mill are recycled and used for pulp production. These are carted to a pulp mill where the papermaking process begins.