Kauri (Agathis australis) is an endemic tree species of New Zealand belonging to the family of the Araucariaceae. Leaf and bark litter of kauri trees decompose slowly. Due to this slow decomposition under mature kauri trees, thick layers of litter and humus accumulate. It seems that the thick and acid organic layer leads to leaching and podzolization of the underlying soil, making the soil less fertile. Questions that we are working on are: * Do the high polyphenol contents result in a slower decomposition of the litter? * Do kauri seedlings survive on the litter cone and do seedlings of competing species survive? * Is kauri able to take up organic nitrogen and are competing species able to take up organic nitrogen?