Forests for Paper
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We take a look at the way that seedlings are grown in a nursery, how they are transplanted into a tree plantation and the way that the mature trees are harvested and processed – a fascinating attention grabber.
Hi there, today we’re visiting the Kwa Zulu Natal midlands, to see the way that commercial plantations or tree farms for wood production are grown and managed in South Africa. This tree farm is owned by SAPPI and they’ve allowed us to come and have a look at their operation.
SAPPI owns and manages over half a million hectares of commercial plantations in South Africa which they farm to provide wood for their paper and specialised cellulose plants. They harvest trees daily and replant the land with new trees.
A modern commercial plantation of commercially grown trees starts in the nursery. We’re at SAPPIs Richmond Nursery near Pietermaritzburg. Composted Pine bark is used as the growing medium for new seedlings.
This bark was removed from pine trees when they were harvested and allowed to break down into a compost which has all the nutrients and other requirements necessary to grow a new tree. You don’t have to grow pine trees in pine mulch – these are gum tree seeds. They’ll germinate and grow into tall gum trees that will be harvested for their wood fibre and cellulose.
Once the seeds have been sown into plastic seedling trays they’re placed into the germination chambers for three days at 25° Celsius and in very humid conditions. These controlled conditions help the seeds to germinate within three days.
The trays are then moved into the nursery where they looked after until the seedling takes its first steps to becoming a tall tree.
Gum or eucalyptus trees take three to six months to develop into a seedling that is strong enough to be planted in the open plantation. Here we see six month old trees, they’re quite bushy. At three years old they’re more upright, with the characteristics of the tall gum tree and at seven to ten years of age they’re ready to be harvested.
Harvesting is done by teams using chainsaws on hillsides and in flatter areas this awesome harvesting machine is used.
With an enormous circular saw at the bottom and two pairs of arms to control the tree trunk, the harvester is able to handle a number of trees in one pass.
The operator sits in air conditioned comfort In the enclosed cabin as the machine rips clouds of sawdust into the hot and humid Kwa Zulu Natal air.
These gum trees will be used to produce cellulose, which can be found in many of the items that we use today.
We have a movie showing cellulose manufacture, so have a look at that to find out more about cellulose.
Pine trees are harvested in exactly the same way for paper and lumber use.
Modern machines can drag a stack of trees across the forest floor to the de-barking and chipping machines. The trunks are fed into de-barker where the bark and branches are removed.
Inside the machine a series of chains and saw blades remove the unwanted parts and feed the naked trunk of the tree straight into the huge chipper machine.
In the chipper incredible power shreds the tree in seconds, spewing out a stream of white chips of wood.
Huge truckloads of chipped gum wood will shortly take to the roads and head for the production plants.
Now that’s impressive isn’t it, absolute raw power in these machines, they make short work of harvesting trees.
Many highly qualified and able South Africans work in the nurseries and in these Sappi commercial plantations, careful planning and expertise ensures that Sappi plants more trees in these plantations every year than it harvests.