For more than a quarter of a century the farmers and landholder of the QE2 Trust, along with DOC and a host of NGOs, have been doing Trojan work getting rid of feral plants and animals so they can begin to put the right native trees back in the right places.

One of the most spectacular projects to date is a 40km long mouse-proof  fence  surrounding the upper catchments of a number of small mountain streams at Maungatautari. In the absence of millions of these little nibblers, the native forest is regenerating fast. Good news indeed.

Forests perform a number of crucially important environmental tasks using only solar power, water and recycled minerals. Trees help hold carbon rich living soils safe from erosion, thus saving rivers and inshore waters from siltation and pollution.

Trees provide shade, windbreaks and a range of habitats both above and below ground, habitats for everything from nitrogen fixing bacteria, soil micro flora and fauna through all the birds and animals of the native bush. Trees control peaks and troughs in river flow helping to ameliorate the effects of floods and droughts.

The removal of native forests and other natural types of vegetation has put a massive strain on the balance of New Zealand and indeed the biosphere over what can only be called the past seven decades of destruction.

Little wonder then that the World Bank has just agreed what the real conservation movement has been saying for more than 50 years – stop the destruction of old growth forest now.

They have even put stock market values on it. The bulk of rainforest land without its trees is only worth between U$200 to US$500 per hectare as pasture. Yet it could be worth between $1500 to $10,000 if left standing to continue all these good solar powered services, balancing the cycles of the living world.

They also said this would be much better use of a ‘carbon market’ than trading the right for firms and nations to continue to pollute the atmosphere with tail pipe emissions.

Humans only appeared on the earth 125,000 years ago and there are already more than 6.6 billion of us trying to make a living. That means the soils of the earth must now be sustainably managed to provide around 19 billion meals every day. Soil is one of the world’s most precious resources and it must be treated with care.

After years of abuse the tide is having to turn for much of our soil’s rich carbon content has been lost to oxidation and erosion. This has reduced the soil’s natural fertility, its capacity for water retention and destroyed its living structure.

In the quest for sustainability as the world faces up to peak oil, rising competition from overseas, proposed flatulence and food mile tax scenarios, farmers are leaving the land or turning to what can be only called the essentials of sustainable agriculture.

This means micronutrients from rock dust, organic fertilizers from fishery waste and strand line seaweeds, all of local provenance and husbandry that doesn’t cost the earth or suck your aquifers and reservoirs dry.