Why branch out into foreign trees?

THE Woodland Trust for Scotland is right to challenge the report by Professor Sir David Read ("Plant foreign trees to save our forests", News, 7 February), and Forestry Commission Scotland has rightly been more cautious in its appraisal of his recommendation.

We already have a wide and diverse range of tree species in this country; native, exotic and naturalised. For every exotic tree species used successfully in commercial forestry, there are many others in policy woodlands or other collections that never quite made the grade, or turned out to be downright disastrous.

Trees take a long time to grow and evaluate and they must ultimately fulfil some useful purpose too. We don't have 40 to 50 years to evaluate new species. We need to work with the ones that we have got and already know about, both native and already introduced species. The Scottish Forestry Strategy of 2006 suggests an increase in cover of native species to 25 per cent of the total.

Native species such as birch, ash and Scots pine have never been artificially bred and retain a wide genetic variability, and can evolve and adapt to whatever new climatic conditions might arise, within limits. Newly introduced species must by necessity be collected from a much narrower genetic base, and are much less versatile because of this, and much more susceptible to unforeseen pests or diseases.

Native species ultimately give us more and better options. We know how they reproduce, we know what conditions they will tolerate, we know what we can usefully do with them. And we also know the strengths and weaknesses of the other main existing forest species. Why risk time and our finite resources on anything else?

Victor Clements, Scottish Native Woods, Aberfeldy