As trees grow, forests evolve
The miracle of the forest’s life cycle is predictable
Forests are dynamic. While trees go through the natural process of growing -- from seed, to seedling, to maturity and eventually death and decomposition -- their forest home evolves. Forests move through a predictable cycle and undergo changes that create the conditions for different communities of plants and animals. Each stage of the cycle lays the groundwork for the next. This continual change is called “succession” as illustrated below.
Only a small percentage of seeds that burst from cones take root in the forest. Young seedlings grow slowly until they overcome surrounding brush, receive full sunlight, then grow rapidly. Over decades or centuries, growth slows and trees become weak from disease, injury, fire, overcrowding or insect attacks. Eventually trees die and decompose or are removed by fire or logging. This makes way for the cycle to continue and new trees to grow.
Forestry science is based on the natural life cycles of trees. Because the stages of succession are constant and predictable, foresters can mimic nature and create a “disturbance” that speeds up or slows down the natural lifecycle stages. Foresters use management tools such as logging and fire to meet the goals of forest owners and to keep forests healthy and growing.
FOREST FACT: Did you know there are male and female pine cones? Male pine cones have close-knit "scales," that hold pollen sacks; female pine cones have looser scales and lie lower on a tree to make pollination easier. Pine cones produce millions of seeds, but only a few germinate and grow into seedlings.