Pterocarpus, a Rainforest Tree

 Trees are the foundation of the rainforest. Without trees, there would be no forest in rainforest, just rain. And all that rain is very hard on the ground when there are no trees, and causes a lot of erosion.

This tree is Pterocarpus, a special tree because of its bizarre roots above the ground. These "buttressed" roots spread out in all directions from the trees. Pterocarpus uses these spreading roots to capture nutrition from the ground a long way from the trunk.

Tropical rainforest trees often have spreading roots. It is different than trees in the United States, in what is called a temperate forest. In a temperate forest, trees need to send a root deep to get water and have one big root going down with small roots going to the sides. In the rainforest, there is a lot of water so they don't need the big root going down. But there is little nutrition in the soil, so the tree must spread its roots out in search of nutrition.

Copyright 1997-2007 Gerald R. Urquhart. For information on using this website in your classroom (which is free and highly encouraged), please contact Dr. Urquhart by email, Also, please send any comments or corrections to Dr. Urquhart.