logo.gif

Cypresses get a boost from FRR Diverse Species Programme

For quite a while, cypresses have been on the verge of becoming New Zealand's third major species, but they have been held back by the poor choice of genotype - in particularly with regard to canker resistance. With new knowledge on how to make a vast range of clones and hybrids - some of them intergeneric as well as interspecific. - there is real potential for an expansion of the cypresses.

Under the FFR Diverse Species programme Scion has successfully developed a hybrid from the canker resistant 'ovensii' Leyland clone and there is potential to hybridise the canker resistant C. guadalupensis with the well-known C. lusitanica - the seed of this hybrid is just as viable as from pure lusitanica, and a hundred times more viable than from ovensii clones.

Although cypresses have been propagated vegetatively for centuries, large-scale clonal trials only started in 2001 and good comparisons are only now being made.

Further trials have been established to test the best C. lusitanica and macrocarpa clones and intergeneric hybrids of C. lusitanica x C. guadalupensis, C. lusitanica x Ch. nootkatensis, and C. macrocarpa x Ch. nootkatensis The programme will continue to make more hybrid crosses, including C. macrocarpa x C. guadalupensis (this combination is absent in the above hybrids). Some canker-resistant C. macrocarpa has also been identified and this will be used for making hybrids. Another clonal trial is planned for 2011.

There is one further development with cypresses. A new web-based cypress calculator has just been released and will be delivered to members via www.ffr.co.nz. It will give predictions of stocking, height, basal area and total standing volume. The calculator is set up so that the user defines the site index or the starting conditions of a stand, thinning regimes, stand information (e.g. area, altitude), discount rate, land values and overheads; the calculator then provides estimates of the mean top height, stems per ha, basal area and standing volume. The calculator will also provide volume harvested, gross value of the stand, as well as Net Present Value (NPV) for a specified discount rate and the internal rate of return (IRR). This exciting development is aimed at better management and better outcomes from growing this very promising tree.

Below is a screen shot of the new Cypress Calculator.