Farm Forestry New Zealand

Woodside: A small forest managed on multiple use principles

John Purey-Cust, New Zealand Tree Grower February 2017.

This is a remarkable book. A noted forest ecologist, a specialist in the New Zealand southern beeches, decides in mid-career to put his knowledge into practice, buys a piece of derelict beech forest which has suffered all the evils that God and man could throw at it and sets about putting it right. Forty years on he writes about how it turned out and in doing so produces New Zealand’s first manual of forest management.

Over the years I have heard Woodside forest discussed from many angles. Is it farm forestry, because if so, where is the farm? A leading forestry academic pronounced its management methods unsuited to radiata pine, and the general consensus seemed to be that it would all, the radiata in particular, blow down.

It was when I attended a field day trip to Woodside as a part of the 2008 North Canterbury Farm Forestry Conference that I began to understand a little better what was going on. I was not alone in my interest. The day was very well attended and the sun shone, but field days can be deceptive. There is only time to see and discuss a part of things, and if they are complicated as they usually are, it is easy to miss key points. So Woodside the book comes to me as the final step in understanding, pulling all those threads together into one logical whole.

Woodside forest

In 1973 John Wardle and his wife Rosalie bought 121 hectares of abandoned land in North Canterbury which was providing summer grazing for about 80 sheep and reverting back to its former black beech forest cover. The land sits on the foothills of the Southern Alps with an altitude range of 400 to 500 metres above sea level. The temperature is described as mild and the rainfall well distributed, but there are regular hazards of heavy wet snow and violent northwest winds.

Woodside is an account of how John and Rosalie turned it back into a living and sustainably managed production forest, giving them a home and income along the way. The over-riding objective from the beginning is ecological improvement. Beneath that, the production objective is top quality saw logs.

For the 84 hectares of black beech which must be retained, and the 27.5 hectares of radiata pine there is too much site variation to allow for a consistent yield based on area or age, so a continuous canopy, single stem management system has been devised. The system has the added advantage of yielding a continuous flow of high quality logs.

Final crop trees are felled at a diameter breast height of 45 centimetres for the beech and 60 centimetres for the radiata pine. The approximate felling age for the beech works out at about 60 years and for the radiata pine 30 to 35 years, with annual allowable cuts of 780 cubic metres for the beech and 935 cubic metres of pine. There being no market for beech logs, they are sawn on the property and sold as sawn timber.

Both species are regenerated naturally, supplemented by planting where needed. Pruning and thinning are both practised, the schedules being described in the book.

Another arm of income is beech honeydew, the waste product of insects which feed on the beech trunk. Domestic honey bees collect this, so the forest owner has the opportunity to have their own hives or to rent the collection to others.

Five hectares remains in pasture for a small flock of sheep, given permanent residence for weed control.

The book closes with a final economic analysis of the fruits of the Wardle’s labours and finds them profitable Surprisingly to me, the largest contributor is sawn black beech at $3,364 per hectare per year, versus $707 if sold as logs.

Where to now?

Single tree selection forest management evolved more than a century ago in the communally owned conifer forests of the French Jura. We were told, when I visited the area as a forestry student in the 1950s, that the prime reason was economic – the local industry was musical instruments and the quality of wood from small group clear felling, which was the conventional practice, had not produced sufficient logs of the quality required.

From memory of that distant visit our juvenile arguments eerily mirrored those of the 2008 visit to Woodside – too expensive, impractically complicated, and it will all blow down anyway.

Woodside the book sees things differently. For the radiata pine it finds a higher effective stocking rate, a good growth response by second tier trees after the felling of dominants, an increased yield with a larger share in higher grade logs, and abundant regeneration. Even the threatened wind blow is seen to be within the conventional risk to the forest – and because of the permanent roading system it is all salvageable.

How small?

So the system works, but where else in New Zealand is there a case for its use? Our existing system of plant and clear fell works well enough for the largest forest owners, and we seek to simplify it further by dropping any practice in between such as pruning. There is no search for quality. Indeed, the present system dilutes it. Therefore, a market gap opens for smaller growers who cannot do much about volume. Quality and consistency of supply is their niche and high grade saw logs their opportunity. But how small is small?

As Woodside shows it can start off pretty small – 27.5 hectares of radiata pine, and 67 hectares of an alternative species, in this case black beech, with no log market but sawing yourself to create one. Continuity of supply is needed and given.

We have communal forests as well − think Dunedin City Corporation and plenty of others, where the citizens might withhold their mandate for all or part of the estate if it involves management practices they disagree with, or where sites of special interest intrude.

Much was made recently of the harvest problems at Glendhu forest in Otago where planting had overlapped the water distribution systems built to supply the Gabriels Gully gold field, an important archaeological site. Continuous canopy single tree management might well be the way to manage that.

Clear felling is the Achilles heel of the plantation forestry system, widely disliked. The forestry profession cries ‘there is no alternative’ but the whistle has blown, now everyone knows that there is. Single stem closed canopy management is not the answer to every situation but, as this book shows, it is time for the profession and the Forestry School to sit up and take notice.

Farm foresters and others alike will welcome this book, and not only because it offers a better way ecologically and a pathway to greater profit for the small grower. It also offers an interest and challenge which the corporate model totally fails to offer.

Long live Woodside.