A totara, torn apart by strong winds

A fierce storm delivered us a sharp reminder last week. Avoid forked trunks in trees. Half a totara split out entirely. It had stood and grown for fifty years. Alas, early in life, the trunk had divided into two leaders and that meant a major structural weakness. The wind tunnel created as a result saw a triple trunked Picea omorika drop one of its leaders. It too was over fifty years old. Early intervention on both trees would have saved us a great deal of work and ensured that what remained was in better shape.

In years of retailing plants, I saw countless people debating over the selection of trees and seeking advice as to whether one tidy little specimen was going to be better than another equally tidy specimen of the same variety. It was very hard to sell a plant with what we call a hockey stick bend at the base. Sometimes this can occur with budded or grafted plants. I rarely bothered trying to explain that a hockey stick on a tree where the trunk is 2.5cm through will not be an issue at all when the trunk is 25cm in diameter. It may be true but it sounded too much like hard sell. The same goes for minor kinks in trunks on juvenile plants. They don’t look the best for the first year but it is not a long term problem. However, forked trunks are a different matter.

The dreaded hockey stick shaping

We are too cavalier in our attitude to trees in this country. Notwithstanding the customer angst about small imperfections, most people spend a great deal more time choosing the right carpet or curtains for their house than in deciding an appropriate variety of tree. Yet those furnishings will long have deteriorated to shabbiness and need replacing before a beautiful tree reaches maturity. You can’t magic up maturity in trees but they are frequently treated as disposable commodities. A combination of ridiculously cheap prices and extraordinarily rapid growth rates in this country has devalued them in the eyes of many.

That said, by no means are all trees equal. City council regulations which set a height above which resource consent is required before trees can be touched have an inbuilt contradiction. Such a rule catches all – trees worth protecting and valuing, trees simply planted in the wrong places and cheap nurse trees of neither long term value nor aesthetic merit.

There is no substitute for a little knowledge. Making an unwise choice may only cost a few dollars at the time of purchase but if it is a rapid growing, brittle variety or one that is shortlived in our conditions, you can pay dearly when it outgrows its allotted space or, in the case of filler trees, outlives its use. Not everybody has a handy person on site with chainsaw, trailer and mulcher and it is very expensive if you have to pay somebody to come in and do it for you.

The forked trunk - an inherent structural weakness

Similarly, planting trees and leaving them to their own devices can cause major issues further down the track. For the want of a five minute job keeping our Picea omorika and totara to single leaders some fifty years ago, we have faced a cleanup taking at least two days. Some trees naturally multi trunk like an overgrown shrub but most are better kept to a single leader. The sooner you carry out the shaping on such trees, the easier it is. At the really early stage, you can do it with secateurs. Select out the better or best looking leader and either remove competing growths entirely or shorten them to reduce competition for dominance. The longer you leave the situation, the more major the progression of tools becomes – to loppers, a pruning saw and then a chainsaw. Never having mastered the chainsaw, I am a strong advocate for a good quality pruning saw.

While some respond to these issues by deciding that trees are altogether too much of a potential problem and nothing will be allowed to grow beyond two metres in their garden, thank you very much, I would urge you to look beyond these gardening Philistines. I do not think any garden or landscape is complete without trees. It is just a matter of choosing the right ones appropriate to the situation and looking after them while they get established. Spend at least as much time on finding out about suitable selections as you would to choosing something major for your house. I try not to bag garden centre staff, but you might be placing altogether too much trust in many if you think they can give you expert advice on trees as well as on carrot seed. Either find someone who is genuinely knowledgeable or look to books. Some of the very best gardening books I know are about trees and one of the strongest and most knowledgable international horticulture societies is devoted to trees – the IDS or International Dendrology Society. The information is there to find.

Few of us will leave any legacy of note when we shuffle off the mortal coils. But good long term trees planted in the right situation and cared for during the early years of establishment are a fine legacy, to my mind.

Felling of the Picea omorika by strong wind

Recommended books on trees include:
New Zealand’s Native Trees by John Dawson and Rob Lucas (Craig Potton Publishing)
New Trees. Recent Introductions to Cultivation by John Grimshaw, Ross Bayton and Hazel Wilks (Kew)
Trees and their Bark by John and Bunny Mortimer (Taitua Books)
Trees and Shrubs for Flowers/ Fragrance/ Foliage. 3 volumes all by Glyn Church (Batemans)

First published in the Waikato Times and reprinted here with their permission.