When seven-year-old Sarah Choat planted trees in a Waihi reserve she never imagined that 21 years later it would play a significant role in establishing national standards for carbon credits.

Sarah planted the trees as part of her school's involvement in Hauraki District Council's Millennium Forest project back in 2000.

Now towering over her, the forest's diverse range of native plants on the corner of State Highway 2 and Heath Street in Waihi turned out to be just what the nationwide Trees that Count Research project needed.

The goal of the two-year project is to confirm how much atmospheric carbon dioxide is taken up by trees, grasses and other plants through photosynthesis and stored as carbon in trunks, branches, foliage, roots and soils.

The site's location near a busy state highway, and that researchers could verify exactly how old the trees are, made it perfect for the trial.

Hauraki District mayor Toby Adams says the government used the information gathered to help set its policy for carbon credits.

'It's well known that planting trees is one of the best ways to offset carbon dioxide emissions, but this research has helped determine how much carbon is absorbed and how many trees are needed,” he says.

The Millennium Forest is one of many tree-planting projects council has undertaken in collaboration with volunteers, groups like Habitat Enhancement Landcare Protection and Waikato Regional Council's Enviroschools programme.

This month Waikino School students and volunteers planted 1790 plants at the Waikino Domain and pupils from Paeroa schools put 350 trees in the ground alongside the Aorangi stream.

To help fund the projects council received $10 000 from the Waikato Regional Council's Environmental Initiatives Fund, on behalf of Paeroa's Streamcare and the Waikino Domain Committee.

Council's parks and reserves team also provide support in the form of equipment, plants, labour and maintenance for these community led initiatives.

For Sarah, the opportunity to participate in the Millennium Forest project is a reminder that you're never too young to make a difference.

'I know this new generation of students will be as proud and amazed as I am at the positive impact their efforts will have on the environment. It's made a tree hugger out of me,” says Sarah.