Farm Forestry New ZealandA true "stringybark" eucalypt, this species has been widely grown throughout Northland with good success. From coastal New South Wales and Victoria, E. muelleriana is well suited to Northland's climate with some very large trees grown and harvested in Northland. Fairly good growth rates and a very narrow sapwood band offer good productivity and a quality hardwood with moderate durability and good strength properties. Durability and mechanical properties improve with tree age. Slightly faster growing than E. globoidea. Suitable for flooring, decking, appearance joinery and structural applications.
Health: Relatively resistant to insect pests and with no health problems in Northland.
Timber: Medium density. Similar to E. globoidea and E. pilularis, a moderately durable light brown heartwood with good strength properties. The sapwood band is narrow and sapwood is resistant to lyctus borer attack. Compression core is negligible and sawn recoveries are high.
| Species | Density (dry) | Bending strength, MoR (MPa) | Stiffness, MoE (GPa) | Hardness, Janka (kN) |
|---|---|---|---|---|
| Eucalyptus muelleriana | 675 | 100 | 13.5 | 6.75 |
Siting: Requires free draining soils of moderate fertility. Reasonable wind tolerance but stem breakages can occur in sites with high wind exposure.
Steep slopes: Well suited to steep erodible slopes provided soil drainage is good and fertility reasonable. 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.
Species characteristics: Some sinuosity and sweep can occur in the stem. Because the available seedlines are unimproved, a high initial stocking is recommended, or alternatively form pruning practiced to remove multiple leaders and retain a single leader in crop trees.
Recommended regimes: Plant at 1600-2000 stems per hectare. Thin in 3-4 stages down to 400-600 stems per hectare. This gives a 4:1 thinning ratio. Because available seedlines are unimproved, a high initial stocking is recommended for a sufficiently high thinning ratio and greater selection for growth and form. Lower tree stockings require costly form pruning for sufficient quality in residual crop trees.
For clearwood production prune potential crop trees to 6-8m in 3-4 lifts and thin down to 300 pruned stems per hectare. However, although pruning improves grade recoveries from those logs, this is not necessary to produce clearwood because eucalypt trees self-prune provided tree stocking is sufficiently high to induce this. The tradeoff is between the cost of pruning and higher establishment costs. A higher thinning ratio also provides greater selection for growth and form.
Key message: A well-proven performer in Northland producing valuable hardwood timber.
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