Mechanical Land Preparation

Mechanical Land Preparation is undertaken if required to address weed competition, impacts of frost, slash deposits (from the prior forestry cycle), compacted soil and poor drainage to improve tree growth and reduce crop mortality, and to mitigate the risks of soil movement and sedimentation.

-  Erosion on steep land
-  Sedimentation
-  Indigenous vegetation and fauna disturbance
-  Reduces soil compaction
-  Targets drainage to safe areas
-  Improves continuing site productivity.

Afforestation

Afforestation applies to new planting where there has been no previous plantation forest, or where there was previous plantation forest and 5 years have lapsed since the last harvest.

It is usually done manually, although mechanical tree planters may be used where site conditions permit.

- Erosion on steep land
- Landscape and amenity effects, such as shading
- Wilding conifer spread

Pruning and Thinning

Pruning removes branches from the lower sections of the tree.

Thinning is selective removal of trees within a stand to achieve an optimum stocking rate for the final crop. This reduces competition for sunlight, water and soil nutrients, allowing the remaining trees to grow more quickly.

Pruned material (slash) is typically left on the ground for weed and erosion control.

-  Heavy rainfall may mobilise slash which can enter waterways causing hazards to infrastructure and scouring of waterways. 

Harvesting

Harvesting involves felling trees, extracting them, processing them into logs, and loading the logs onto trucks for transportation. Clear felling (felling the entire stand of trees) is the most common type of harvesting in New Zealand.

- Soil disturbance
- Sedimentation
- Indigenous vegetation disturbance
- Riparian vegetation disturbance
- Slash

Earthworks

Earthworks are undertaken to provide the physical infrastructure required to establish, maintain and harvest a plantation forestry, including the construction and maintenance of access roads, processing areas, landings, river and stream crossings.

-  Erosion
-  Sedimentation
-  Indigenous vegetation disturbance
-  Targets drainage to safe areas
-  Facilitates harvest layout to reduce effects associated with log extraction