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After centuries of contraction, old growth forests are on the increase again in some countries round the world.

The keys to the resurgence of some of the best–loved and most venerable forests are a strong economy and an increasing skill at managing them for “old growth” characteristics as well as for timber production, Professor Juergen Bauhus of Freiburg University told the Old Forests, New Management conference in Hobart on 21 February 2008.

“One of the most interesting developments of recent years has been the expansion of old growth forests in regions such as North America and Europe” Prof. Bauhus says.

“This is nearly always the result of a strong economy.  There is a distinct pattern emerging in which the forest area shrinks and the forest density declines as a country industrialises, which recovers again as its wealth increases.”

It is also the result of a trend towards managing forests for what Prof. Bauhus terms “old growthness” – the salient characteristics of old forests, such as having numbers of large or dead trees and the ability to safeguard rare and endangered species.

“Old growth means different things in different places. In parts of North America it may mean the open forests of Ponderosa pine that were fire-managed by the native Americans.  In Europe it may mean the great oak forests that were planted in the Middle Ages to feed pigs and to supply timber for ships. These are termed “cultural old-growth forests”, which are also very important for biodiversity and other values. In Australia it may mean forests that have been undisturbed by human activity for long periods.

“But whatever it means, we are now realising that some of these old-growth elements and structures can be included in a forest managed for timber production. Here, they may even be better protected than in inaccessible forests left completely alone, which could be destroyed by a catastrophic wildfire.”

The new approach, which he terms ecological silviculture, calls for much greater involvement by local communities in reaching agreement about the values for which the forest is to be managed, in order to strike the correct balance, he says.

“I wouldn’t say you need to actively manage every bit of old growth forest.  You should certainly leave significant stands or buffer zones untouched.  But you need to agree on the goals for which the forest is being managed – and on the tradeoffs that will be involved in achieving them.”

For example, he says, a decision to leave a large area of old growth unmanaged may involve the trade-off of having more plantations in the local area to supply the timber.

“In the end it boils down to having a shared vision for your landscape,” Prof. Bauhus says.

Today many countries enforce rigid policies which prevent a loss in old forest area. These plus economic affluence and greater farming efficiency are creating the opportunity for the forests to expand once more after generations of contraction.

“And as our silvicultural skills increase we can manage these forests to retain the features which we associate particularly with old growth, whatever that means locally.”