Farm Forestry New ZealandKahikatea is a fairly slow growing native conifer species well suited to infertile sites, especially those with poor soil drainage. Where correctly sited, kahikatea has been fairly reliable in Northland plantings and survival good. The species has a narrow conical form and is straight.
Health: Healthy with no significant pest problems.
Timber: Heartwood is white to pale yellow-brown and sapwood is white and very wide. Sapwood is highly susceptible to borer but can be treated with boron salts. Fine and even in texture and straight-grained. Holds nails and screws well, easily worked. Kahikatea's resistance to splitting allows it to be machined and turned without difficulty into mouldings, joinery and turnery. Kahikatea's rather flat appearance and lack of colour may limit its appearance applications, but the non-tainting properties of the timber have been and can be used for applications associated with food. Potential for plywood, decorative veneers and boatbuilding.
The wood is easily dried but highly susceptible to sap stain. Kahikatea wood cannot be adequately pressure treated with CCA preservatives for in-ground use. Similar to radiata pine in structural properties with a good strength to weight ratio. Good bending and gluing properties.
| Species | Density, dry (kg/m3) | Bending strength, MoR (MPa) | Stiffness, MoE (GPa) | Hardness, Janka (kN) |
|---|---|---|---|---|
| Kahikatea | 450 | 75 | 10.7 | 4.2 |
Siting: Prone to compression wood on exposed sites. Well suited to poorly drained sites of low natural fertility. Responds well to improved fertility.
Steep slopes: Suitable for planting on sites too wet for totara.
Species characteristics: Not a particularly exciting timber for modern applications, but among the few conifer species suited to poor fertility waterlogged soils.
Recommended regime: Regular releasing from weed competition is necessary for good growth rates. Recommended planting of 1600-2000 stems per hectare, or alternatively 800 stems per hectare interplanted with 800 stems manuka per hectare for honey production and as a nurse crop to draw the kahikatea upwards.
Key message: Not a fast-growing species, heights of 4-6 m can be achieved in 20 years.
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