This tree is approximately 100 years old. Imagine it is about 20 metres high and has a crown diameter of about 12 metres. With its 600.000 leaves it multiplies its 120 m2 ground cover 10 times up to 1200 m2 surface of leaves. Due to the aerial space in its crown, a cell surface is created of approximately 15.000 m2 (2 football fields!). On a sunny day this tree processes 9400 litres of water and 18 kilos of carbon dioxide. That corresponds to the average carbon dioxide expelled by 2,5 family houses. To achieve this, an enormous amount of air should flow between the leaves, together with the bacteria, mushroom spores, dust and other detrimental substances that will mostly stay behind on and in the leaves. Meanwhile this air becomes damp, because the tree consumes and evaporates approximately 400 litres of water on such a sunny day. The 13 kilos of oxygen that are formed by means of photosynthesis as a by-product, cover the need of approximately 10 people. On a day like this the tree produces 12 kilos of sugar for itself, from which it forms all its building materials. It stores a part of it as a reserve and from the rest it formes new wood. If this tree would have been cut down, then approximately 2000 young trees with a crown content of one cubic metre need to be planted to replace this old tree completely. In 1990 this would have cost approximately 140,000 euros, but nowadays much more.
Data taken from Naturfreunde international 03/89.