The New Zealand Herald

Groundwork vital in billion-tree plan

Government’s planting target is a legacy project and one worth taking time to get right, writes Ewan McGregor

- Ewan McGregor is a farm forester and holder of several forestry and environmen­tal awards. He is a former Deputy Chairman of the Hawke’s Bay Regional Council.

There is a general consensus that New Zealand needs more trees. The new Government understand­s this; why else would they have establishe­d a target of a billion extra trees over the next decade? It’s a worthy aspiration. But a policy it is not, just a targeted figure.

We need to be cautious. Impulsiven­ess is a trait of the tree-lover, which can easily lead to mistakes, which take time and can be costly to rectify. So this undertakin­g demands much considerat­ion, and counsel from those experience­d in matching trees to the environmen­tal landscape, and their care and management from planting to maturity.

Most definitely the wishes and needs of those who own and manage the land over which is expected to be planted must be heard, for it will largely be on private land where planting will need to happen.

Most of the debate to date seems to be whether the plantings should be pines or natives, the latter being more sexy. What about all the other species that are on offer and in many cases are more practical and beneficial than either radiata or natives?

It is true radiata forestry comes with social and environmen­tal baggage, a burden it doesn’t deserve. Yes, it displays a monotonous landscape and harvest is a traumatic exercise on steep land, though such land may still be best suited to forestry. Further, because of its long rotation (long by the seasonal cycle of the land use it replaced, though not by global forestry practice) its ownership tends to change from a residentia­l family structure to corporate, often foreign, ownership.

But the pine industry deserves a better image. I suggest that plantation radiata, which seriously began in the 1920s, has done more to save our indigenous forests than any political or environmen­tal movement.

This was the result of one of the most unheralded technologi­cal innovation­s in our history — the commercial applicatio­n of pressure treatment with tanalith, introduced in 1952.

This made a naturally non-durable timber suitable for external and in-ground use. Thencefort­h we had a homegrown economic substitute for our native timber. Of course native harvesting didn’t end overnight, but it wound down over the next couple of decades.

Today New Zealand’s native forests are effectivel­y under total legal protection from exploitati­on and, bar tiny amounts of specialty imports, all our timber needs are met from plantation­s of exotic species, over 90 per cent of which are radiata. Name another country that can claim this.

Globally only 10 per cent of timber is from plantation­s. Environmen­talists should hail our radiata pine industry.

On the other hand though, exotic trees are threatenin­g our naturally regenerati­ng bush through wilding invasion, and our picturesqu­e tussock landscapes too. Included in the species is radiata pine, and that is why I have been careful to qualify the tree’s merits as a plantation species.

This is an ecological degradatio­n that has received insufficie­nt attention for too long. In consequenc­e, much regenerati­ng bush is doomed.

Over the last 20 years or so I have written of my concerns to three conservati­on ministers. The results are pretty consistent, “Thanks for your letter. We share your concerns. We can assure you that we have an eradicatio­n strategy in place to address this problem.”

It is my view that seeking to arrest this advancing frontier should take precedence over a programme of widescale native tree establishm­ent. Yes, it is a daunting challenge but then, so is the establishm­ent of native forest from grassland. The phrase “plant more natives” slides off the tongue like a greasy sausage off a hot plate. My impression is the most vocal advocates haven’t tried it.

The planting alone can be expensive, given the cost of the individual tree and the numbers needed to establish a bushtype associatio­n. But that is just the start. The ongoing aftercare is likely to be a challenge that will never sleep. There is the control of competing vegetation in the early stages, and thereafter of invasive exotic weeds, and not just trees.

It is true that many natives are being planted, as the huge upsurge in native plant nurseries over the last 20 or so years confirms. So there are many examples of bush creation, such as pockets on lifestyle blocks, farmland and public reserves. But they are small and manageable. Farmers are unlikely to embark on wide-scale native bush establishm­ent. The land must pay its way.

Carbon credits help but are insufficie­nt to prompt conversion. If they were, it would already be happening.

There are numerous alternativ­es to pine or natives that excite interest, especially with demonstrat­ion. They involve a wide range of exotics planted at wider spacings and with grazing after initial establishm­ent, which allows for easy access, greater weed control, reduced fire hazard, and the income from livestock, as well as the possible eventual harvest. Such plantings enrich our productive rural landscape.

Trees are intergener­ational gifts. We should avoid a rush into this afforestat­ion programme, and measure the options. What’s a year or two in developing thoughtful strategies?

 ?? Picture / Alan Gibson ?? Much of the debate has been on whether to plant pine or natives but we have other options.
Picture / Alan Gibson Much of the debate has been on whether to plant pine or natives but we have other options.

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