Forest Life Cycle Cards
During an unusually hot and dry summer, a forest fire swept through a watershed and killed most of the old trees in the forest.
The fire opened the Lodgepole pine cones and released some seeds onto the bare soil. Other seeds blew in from the nearby unburned forest. - Thousands of new lodgepole pine seeds, survived and began to grow in the open burned area. The lodgepole seedlings are the pioneer species, or first species to move into an area after a fire, other soil disturbance.
The Douglas fir seeds that blew into the hot open area, died under the harsh sun. The lodgepole seedlings grew quickly and within a couple of years formed a thick, shady covering over the forest floor.
In the shade of the lodgepole seedlings, with extra protection from a nearby log, one Douglas fir tree seed sprouted and began to grow.
Through the next 100 years, the Lodgepole pines grew straight and tall. Some trees fell over in wind storms and some died because they didn't get enough sunlight. The Douglas fir tree continued to grow under the protection of the lodgepole canopy.
As the Lodgepole pines died, sunlight was able to reach the Douglas fir growing below and allowed this tree to grow above the canopy of the Lodgepole pine trees. When our Douglas fir tree was 150 years old, it was 90 feet tall and 6 feet around. Lots of animals lived in is branches.
Hikers often stopped to admire its size and uniqueness there amongst the lodgepole pines.
Lightening hit our tree on its 160 birthday and killed the top of the tree. A new top grew from a side branch.
When our tree was 200 years old, a severe wind storm blew over several neighboring Lodgepole pine trees, and one crashed into our tree on its way to the ground.
The tree hit the trunk hard enough that the protective bark was removed near its base, making a wound 6 inches wide and 12 inches long. The wound in the tree attracted wood boring beetles that chewed their way into the wounded area.
A fungus grew where the beetles had made holes in the tree. The fungus continued to grow and spread up and down the trunk decomposing the tree's cambium, or living inner tissues.
By the time our tree was 260 years old, it had a weak spot in the trunk where the fungus had eaten out the middle of the tree. Carpenter ants moved into the weak spot. A northern flicker, a common woodpecker here, pecked holes in the tree to get to the carpenter ants.
10 years later, another fire burned through the area. Our tree, in its weakened condition, was not able to survive the bum. Although no longer living, the big Douglas fir remained standing in the forest for 50 years as a large snag, or standing, dead tree.
The snag of the old tree began to decompose, creating habitat for many species of wildlife. A pair of great homed owls lived in a large hole near the top of the snag. A flying squirrel constructed its den in a lower branch, and deer mice made small holes in the roots.
The roots of the snag were eaten by a root rot fungus. The rotten roots could no longer support the weight of the huge trunk. The next spring, in the first windstorm, the snag crashed to the ground and broke into several pieces.
The small pieces of the fallen snag slowly decomposed into the soil, providing nutrients for new trees and plants. The large trunk of the old tree, now rotten and decaying, laid on the ground. The old log increased the amount of dead material in the forest and contributes to an important part of the forest life cycle -- fire.