Farm Forestry New ZealandSome of the largest Coast redwood trees in the country are found in Northland. Coast redwood grows well in Northlands humid climate and is relatively untroubled by pests and diseases.
Good growth rates and form are achieved by improved clonal stock. Research is still underway for improved heartwood content and durability.
Health: Relatively untroubled by pests and diseases.
Timber: Redwood timber is red, light and stable. The heartwood is durable above ground and is suitable for cladding and exterior joinery but not very suitable for structural applications because of issues with fixings. A similar timber to Japanese cedar but not strongly scented.
| Species | Density, dry (kg/m3) | Bending strength, MoR (MPa) | Stiffness, MoE (GPa) | Hardness, Janka (kN) |
|---|---|---|---|---|
| Sequoia sempervirens | 380 | 24.4 | 6.6 | 1.9 |
Siting: Requires moderately fertile soils and sufficient soil moisture and depth. Not suitable for exposed slopes deficient in topsoil.
Steep slopes: A coppicing species, i.e. the roots do not die but the stump stays alive after felling and re-sprouts. Coppicing species hold the soil from slipping even after harvest. However, redwood requires adequate soil depth and shelter so not suitable for upper slopes.
Species characteristics: Coppices. Not suitable for exposed and skeletal sites. Pruning requires careful management because of epicormic shoots that emerge from pruning scars. Tall narrow-conical tree that tends to be lightly branched. For this reason stocking does not need to be as high as for other species. Management should avoid overstocking and formation of black (dead, bark-encased) knots, while limiting knot size.
Recommended regime: Plant clonal stock at 600 stems per hectare.
Key message: A reliable choice for lower slopes with a potential market for sawn timber to California.
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