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I well understand people's aversion to large blocks of coniferous forest.

Over the course of a 12 year career as a woodman in the UK, I have spent a total of 2 years working in the forestry and silviculture industry in New Zealand. [Silviculture means the planting and maintenance of timber trees].

In the UK, the management practices in conifer forests are not intensive, and this largely results in average to poor quality timber and large blocks of dark dense forest.

When you see these and the lack of wildlife in them, it is not the fault of the tree species. It is large due to poor management techniques and a high stocking density. The forestry systems in New Zealand are far more intensive and systematic and as a consequence the final timber trees are of the highest quality and value. This also makes them a haven for wildlife.

Because the early settlers decimated the native forests, the majority of the new forests planted and cut for timber are of non native conifers.

The main tree species planted is Radiata pine (Pinus radiata) also called Monterey pine, a native of California. This grows exceptionally well in the New Zealand conditions, and they have also selectively bred variants for high grade timber.

From planting to final felling takes between 20 and 30 years, and the trees are felled when they reach a dbh (diameter at breast height) of 60-80cm which is about the width of a door. The spacing between each tree is a lot wider than in the conifer forest in the UK. This makes the trees grow fatter quicker and also means that the forest have many native species growing in between. For clean, knot free timber which holds the highest value, the lower branches are pruned off in successive stages.

The first pruning lift as it is termed, happens around year 4 of the trees life, and is 3m from the ground leaving a 3m green crown (top). At year 5 pruning lift to 4.5m, leaving a 3m green crown and at year 6 lifted to the final height of 6.5m with a 4m green crown. That means that after 6 years old the tree is already at least 10m (33') tall. This gives an idea of the impressive growth rate.

After that they are left alone till they reach the right dbh for felling. Of course different local conditions and soil types affect these pruning times and growth rates.