[11 March/Stuff NZ]

The mānuka plant could soon be used in improving New Zealand’s freshwater quality. ESR, Waikato Regional Council and local iwi are 18 months into a five year study on the tree to figure out its ability to filter out freshwater-harming nutrients and pathogens. The trial site is on the shores of Lake Waikere. Dr Maria Gutrieerez-Gines, ESR Scientist reports that ESR has been researching the plant for ten years.  She stated that if the same anti-microbial properties found in mānuka honey and oil are also in its roots then it could help reduce nitrates and pathogens in the soil if it were to come into contact. The scientists discovered positive result in laboratory and greenhouse experiments so now have moved onto the real world environment by planting mānuka trees on a four hectare plot of armland. The plot is divided into three sections, a control, one with just mānuka and one with mānuka as well as various other native trees. Run-off water is collected and analysed along with measures of the sites ecology, tree growth and soil samples. Dr Jacqui Horsewell, Scientist at Massey University reported the study could be another tool to help people clean waterways, although the process of improving water quality will take a long time. Director of Nikau Farm Estate Trust, Tawera NIkau said regardless of the result they are going to keep planting and eventually hope to have a 34 hectare wetland created.