Do evergreen trees excrete?
Excretion is the process by which any organism gets rid of waste metabolic products. You will see from this that there are a number of products of metabolism which an evergreen tree does not need. Oxygen is a waste product of photosynthesis. Carbon dioxide is a waste product of respiration. However, when leaves drop from a deciduous tree, they often contain crystals of substances which have been built up over the life of the leaf and these are the products of metabolism. It is not true to say that ALL of the leaves on an evergreen tree remain on the tree for the lifetime of the tree. Leaves are shed and new leaves grow continuously – an evergreen tree however always has some leaves on it, even in the cold seasons of the year. You can find proof of this under any evergreen tree – for example a sprinkling of dead and dry needles under a pine tree or a yew tree.
