A tree is a perennial plant with an elongated stem, or trunk, supporting branches and leaves in most species. They represent the largest and often oldest plants in a fully-developed ecosystem, requiring significant support and time to grow but returning that with proportional animal support and oxygenation.
There are 3 trillion trees in the world now, and some 1 to 5 billion are cut down each year.
|Aquatic Micro-Organisms||Archaea · Cyanobacteria · Diatom · Plankton|
|Algae||Stonewort · Green Algae · Kelp · Seaweed|
|Aquatic Animals||Coral · Crustacean · Fish · Mammal (Aquatic) · Reptile (Aquatic)|
|Terrestrial Micro-Organisms||Actinobacteria · Lichen · Fungus · Protozoa|
|Plants||Grass · Moss · Shrub · Tree|
|Terrestrial Animals||Amphibian · Bird · Insect · Mammal (Terrestrial) · Reptile (Terrestrial)|