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Spectacular growth from Eucalypts

The potential reward of growing eucalypts in New Zealand has captivated a great number of foresters and farm foresters alike. The allure of very rapid growth, high quality fibre, attractive & durable timber along with pleasing aesthetics are just some of the many reasons for planting eucalypts.

There have been many notable advocates in the past for the genus, not least of all Harry Bunn and Neil Barr. The situation is similar today within the membership of the Diverse Species Theme of Future Forests Research. However, with the benefit of hindsight, it's fair to say that the genus has not lived up to expectations yet. As with all generalities, there are notable exceptions and it has been these that have fuelled the continued planting of the genus. Eucalyptus regnans and E. fastigata are promising species which have been planted to a greater or lesser extent over the last 40 years.

Like radiata, these species have their own breeding programmes following the traditional route of provenance and progeny selections & trials culminating in grafted clonal seed orchards being established at Amberley. Increasing quantities of seed from these orchards will become available to growers for new plantings. These species, now into their 3rd breeding generation are being evaluated in progeny trials growing in Compartment 333 Kaingaroa. The growth rates and form are spectacular. On average at age 2½years the regnans was 6.2 m tall (the best family 6.8 m and the worst 4.9 m – which is still impressive). Exceptional trees were nine metres tall and no diseases were apparent. Fastigata while not as vigorous (average is 4.6 m, best family 5.4 m, worst 3.8 m) still impresses and the level of stem malformation (often a significant problem with fastigata) was low at less than 10%. Initialising the Eucalypt calculator with these values results in predictions of a massive 800-950 m³ at age 20. For many reasons, these eucalypts should not be overlooked.

2½ year-old E. regnans – Kaingaroa