Farm Forestry New ZealandEucalyptus microcorys is a subtropical eucalypt from Northern New South Wales. It is considered one of the finest hardwoods in Australia. Because of its reputation tallowwood has been widely planted in Northland, one of the few regions in New Zealand where it can be grown, being frost tender.
Health: Susceptible to possum browsing as a young tree. Few insect or disease problems.
Timber: Medium to high density. The timber is pale brown, hard and very durable with exceptional stiffness and strength properties. Produces high density, durable and strong wood from an early age. Applications include high-quality timber decking, timber flooring, external structural applications (above ground), posts and poles. Sapwood band is fairly wide and sapwood is susceptible to lyctus borer. Sapwood can be treated with boron for internal applications.
| Species | Density (dry) | Bending strength, MoR (MPa) | Stiffness, MoE (GPa) | Hardness, Janka (kN) |
|---|---|---|---|---|
| Eucalyptus microcorys | 750 | 100 | 13.5 | 6.75 |
Siting: Requires shelter from strong winds. Susceptible to frost damage in the first winter following planting, best planted in spring after winter frosts have finished.
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, E. microcorys requires adequate soil depth and shelter so not suitable for upper slopes.
Species characteristics: Slower-growing at first than other eucalypts, but capable of very high volume productions because the crown is dense and shade-tolerant.
Recommended regime: 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: Exceptional timber and with high volume production on the right site.
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