Our woodlands keep on growing

The Independent on Sunday's forests continue to grow. Although our campaign officially ended last month, readers have continued to buy trees in their thousands. The total is now 7,000 - which means that each of our two forests, in Bristol and Shetland, will have 3,500 trees.

The Independent on Sunday's forests continue to grow. Although our campaign officially ended last month, readers have continued to buy trees in their thousands. The total is now 7,000 - which means that each of our two forests, in Bristol and Shetland, will have 3,500 trees.

In Shetland the trees will be planted on the outskirts of Lerwick, the capital, probably by a lake at Clickimin, to the south of the town. It is home to a prehistoric site, a fort and a broch - a round stone tower. The first saplings, to be planted next spring, will be alder and birch which will provide shelter for longer living species including oak, ash and elm.

In Bristol, the trees are being planted in the truly urban landscape of the St Paul's interchange, where 60,000 cars rush every day along the M32 which connects the city with the M4. Some of the trees have already been planted but the bulk will be put in the ground this autumn and will comprise native broad-leaf species, again including oak, elm and ash.

The Forest campaign was launched in February when we bought 750 trees, the number we needed to offset the amount of carbon dioxide we produce in one year. The theory is simple: trees convert carbon dioxide, one of the greenhouse gases associated with global warming, into harmless oxygen and wood.

Readers followed our example in their thousands. Just 15 trees, costing £60 in total, are enough to offset the average person's carbon dioxide emissions for a year. There are also many other equations: a long haul flight from London to Los Angeles requires one tree; five trees offset the typical car's carbon dioxide emissions for a year; seven trees counter the carbon dioxide of a typical refrigerator and eight trees will offset the emissions of the average house's lighting and heating for a year.

During a recent visit to the UN headquarters in New York, Dan Morrell, founder of our planting partner, Future Forests was invited to address a forum on sustainable development in front of more than 200 environment ministers, ambassadors and non-governmental organisations. "We got a standing ovation which was so welcome. I think it was the moment when this idea really took off internationally," he said.

"The idea is one of empowerment. One person doing this by themselves is a drop in the ocean but lots of people doing it adds up to lots of drops. Once you plant trees you start thinking about reducing emissions at source and using renewable energy."

If you wish to buy trees for either of our forests please phone the Future Forests hotline on 0870 241 1932. Everyone who buys trees will receive a certificate and record of their tree. One tree costs just £4.