As we walk through the forest and view the trees, we remember they were once tiny seeds. Nearly all hardwood seeds are the same. They have an outer cover for protection, food and water inside to use for the first surge into growth, a part that has an affinity for water that will seek out the soil and become roots and a part with an affinity for light that will seek the sun and become leaves and branches. Nature gives all seeds another characteristic. An acorn will always grow into an oak tree and a pine seed will always grow into a pine tree.

While nature provides a seed all it needs to survive, she provides great opposition to survival. From the beginning, each seed must compete with its neighbor for water, food, sunlight and space in which to grow. Trees produce thousands of seeds. Very few grow to maturity. In fact, from a start of 10,000 seedlings per acre at age one year, the final stand of mature trees may number less than 50.

Seeds compete not only for food and sun with each other but many are eaten by forest animals, others are destroyed by insects and disease, and some simply do not find a suitable place to sprout.

Some trees produce flowers, from which the seeds come, before the leaves come out in the spring. These flowers produce seeds that ripen in the spring and fall to the ground and start to grow that year. Other seeds ripen and drop off in the fall and lay dormant over the winter and start to grow the following spring.

Temperature is the main factor in starting seed growth. When warm weather comes in the spring and the sun's rays hit the earth at a more direct angle, nature springs to life. Seeds have various means by which they are scattered over the countryside. An acorn falls down right under an oak tree but squirrels will often carry it away and bury it. Some seeds have wings that allow the wind to blow them over great distances. The outer covering of seeds can pass through a bird's digestive tract without damage, and be dropped far away. The maples, the yellow poplar and ash have winged seeds, the wild cherry is a seed spread by birds.

In order for any seed to sprout and develop it must have food, water, sunlight and warmth. Until it gets roots, a stem above ground, and some leaves or needles, the seed uses the food stored in its shell to develop growth. As roots go deeper into the soil they absorb water and minerals form the soil and send these up into the stem.

The leaves act as a chemical laboratory. In a process called photosynthesis, which takes place in the green leaves of a tree in the presence of chlorophyll and sunlight, the tree takes carbon dioxide from the air and manufactures starches and sugars and gives off oxygen as a waste product. The formula is simple but the process has never been artificially duplicated.

For each ton of wood that is produced, a little more than a ton of oxygen is released into the atmosphere. This takes place only on growing forests. In our old overmature forests where growth has become stagnate and decay has set in, more oxygen is used than produced. Thus, from an air quality standpoint alone it is essential to maintain healthy, viable forests in vigorous growing conditions.

In a process called transpiration, a tree gives off large quantities of water through a section of a leaf called stomata. All trees manufacture more food than they need for growing. The extra food is stored in the tree cells for use in the spring when it puts out leaves, flowers and seeds.

A tree grows upward from the tips of the branches, downward from the roots, and outward from the trunk. The roots anchor the tree to the ground, and the trunk gives support to the branches. As the tree grows from the food it manufacturers, it adds new layers of wood to its trunk. Because one is formed each year, these layers are called annual rings, and may be used to tell the age of the tree.

This is a drawing of the cross section of the stem of a tree. The outer bark is dead material, outside protection for the growing part of the tree. Next is the inner bark, composed if living cells through which water and food are conducted down into a tree, giving life to its roots and other parts. Next is the cambium layer, which you cannot see in a cross section without a magnifying glass. The cambium layer is made up of cells, those toward the outside make bark and those toward the inside make wood. Next is the sapwood, also composed mostly of living cells through which food and water are collected by the roots and sent up to the branches and leaves.

The center of the stem is the heartwood. This is composed of dead cells that give the tree strength to stand. The heartwood was once sapwood but when new sapwood formed, the older died and formed the heartwood of the tree.

As you study the cross section of a tree, note that some annual rings are wider apart than others. When you see a wide space between the rings this means the tree grew faster at that time because it got more sunlight, water, and food. Lack of sunlight, food, water and competition with neighboring trees or being subjected to destructive forces such as forest fires, insects and disease, slow down the growth of the tree. The years marking slow growth show the rings closer together and narrow in width.

In Appalachia, a tree's growing season is during late spring, summer, and early fall.