What Is a Forest Canopy?

Structure

• The structure of the canopy is largely determined by the species of trees that live in the forest. A coniferous or pine forest will have a more vertical structure, but broadleaf trees tend to form a single horizontal layer at the top as they compete for sunlight.

Inhabitants

• According to the U.S. Forest Service, nearly half of all known forest organisms spend at least some of their time in the canopy level. Rootless plants, called epiphytes, grow on canopy branches and filter nutrients from the air. A large community of insects live in the epiphytic plants which in turn supports a vibrant bird population as well as other, larger organisms.

Importance

• The Forest Service points out that the canopy is responsible for 90 percent of all the photosynthesis that occurs in a forest. This energy-producing process effectively fuels the rest of the ecosystem. The canopy also prevents harmful pollutants trapped in rain water from reaching the soil and keeps the forest floor cool. The water that trees emit during photosynthesis contributes to local cloud formation.