When a person views the Grand Canyon from the south rim it appears to be a desert down below. For the most part it is. The slopes and mesas abound with desert plants such as cacti, sage brush, juniper, brittle brush, grasses, and many other drought tolerant plants. But hidden in many of the side canyons exist micro-climates of lush plant life. Some are hidden in areas where there is nearly constant shade to prevent the hot sun from baking every living thing. Other micro-climates are caused by spring water which provides the force necessary to supply abundant forbs. In this panorama a small deciduous forest of cottonwood trees and willows abounds. The reason is because at the bottom of this canyon there is a small trickle of water. The water is so sparse that it does not form a constant stream. It flows on the surface where the bedrock is exposed. Where there are deposits of gravel, the tiny amount of water sinks down into it only to re-emerge many yards farther down the stream bed. But, the water is always there in some amount. The small amount of constant water is all that is needed to give rise to a whole different biome within the desert. Even though the flow is small, it cools the surrounding area and allows less heat tolerant plants to grow. The autumn color of the cottonwood trees is a welcome changed from the constant desert view. The large trees also provide a cooler and more protected place to camp. You can view this and many other panoramas of the Grand Canyon at GCPano.org where you will find more detailed descriptions along with topo maps and interactive movement from one panorama to the next. GCPano.org