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Space and Survival - Trees compete for space in the soil for water and elements and for space above ground for the energy of the sun. In the warm rain forests, water is not a limiting factor for growth, nor is temperature. But, space is a limiting factor. Plants grow very close together, and plants grow on other plants-epiphytes such as the many beautiful orchids. Space to produce leaves that can capture the energy of the sun is a limiting factor for survival of all green plants. As space becomes more restrictive, the shape of trees is affected. Branches that grow in a horizontal position will not live long. Trees that develop codominant leader stems before the leaders reach the top of the forest canopy, will not live long. Trees that can reach the top of the forest canopy rapidly, and then produce codominant stems, may grow over other trees, and thus grow to a larger size. The development of codominant stems too early in life can be harmful. When they are developed later in life, they can be beneficial; for a period. And then they become harmful again. The codominant stems provide more leaf surface to capture energy. The codominant stems grow rapidly. The living wood in the stems must get their energy from the leaves. The dynamic mass of the codominant stems increases to a point where energy to power all processes begins to be in short supply. Shedding starts. The tree can still maintain a prime space position as a larger spreading crown develops, so long as shedding regulates the increasing dynamic mass-wood with living cells. Trouble for the tree starts when shade-tolerant trees begin to grow under its large spreading crown.