Forest Ecology

Pre- Activity: The Only Constant in Life is Change

(From Project Learning Tree Nothing Succeeds like Succession)

Overview: “The only thing constant in life is change” by François de la Rochefoucauld.

Students will identify successional stages in a forest.

Length: Approximately 1 hour

Background: Successionrefers to the more-or-less predictable and orderly changes in the composition or structure of an ecological community, usually a forest. It can be loosely referred to as the “life cycle” of a forest. There are two types of succession: primary succession and secondary succession. Primary succession occurs in an area where no soil is present; the original substrate is usually rock or lava. Secondary succession occurs in an area where soil is already present. There are several stages of succession, each indicated by a different community of species.

Materials: Paper

Colored pencils or markers

Handout of succession picture (included below)

Instructions:

1. Ask the students to name ways that a forest might change over time.

2. Read aloud to the students the attached story. Stop after each indicated portion of the story (you’ll see blue directions to “stop here”) and instruct students to draw a picture of this stage of the forest. (You might have them divide their paper into six squares and draw each picture in one of the squares.)

3. After reading the story, discuss their drawings.

4. Hand out copies of the succession sequence to show students how succession typically proceeds in a forest. The picture shows successional stages of a mixed hardwood forest found in temperate regions. Here in southeast Texas, the “young forest” would be comprised of Loblolly Pine, Short-leaf Pine and Water Oak. The “mature forest” would include a mixed forest comprised of Loblolly Pine, Short-leaf Pine, Water Oak, Sweet Gum, some maples, hickory and various oak species. The “climax forest” would include Hickory and Oak species, or Beech and Magnolia along the Gulf Coastal Plain.

Story: Tree Tops Valley

Once upon a time, a boy and a girl lived with their parents at the edge of a beautiful green valley in the Pacific Northwest. Their names were Sara and John. The valley was filled with a vast evergreen forest. Its trees towered over the log cabin where John and Sara lived. Sara and John loved the forest. Every day they went exploring. They paddled in the forest’s cool streams and made trails under the giant conifers. They also liked to have picnics at the top of a hill near their home. Up there, they could look down on the tops of the valley’s huge trees. One day when they were up on the hill, they decided to give the valley a name. They called it Tree Tops Valley.

(Stop here to let the students draw a picture of this phase of the forest.)

Then in the middle of a hot summer day, everything changed. A lightning storm started a fire in the forest. Luckily, the wind blew the flames away from Sara and John’s home. But when the fire went out, they saw it had burned their Tree Tops Valley. All the tall trees were burned. The tender little seedlings that had grown on the forest floor were gone. All that was left was the burned remains of trees. They both wanted to cry. Sara said, “I just can’t look at it. Our beautiful forest is gone forever. I never want to sit on our hill again.”

(Stop here to let the students draw a picture of this phase of the forest.)

After the fire, the family moved away to a settlement where other families lived. There were children there, and Sara and John made new friends. Then five years after the fire, their father said, “Why don’t we visit the valley? It would be good to see it again.” Sara and John didn’t want to go. They remembered how the valley had looked after the fire. But they agreed, and one day, the family saddled their horses and rode up to the valley.

What a surprise! Things had happened since the fire. Wind had blown seeds into the valley. Birds had dropped them from the air. The seeds had sprouted. Now, instead of bare, burned ground, there were mosses, weeds, grasses, and ferns growing everywhere. The children rode back home feeling much better about Tree Tops Valley.

(Stop here to let the students draw a picture of this phase of the forest.)

The years went by. Before they knew it, Sara and John had grown up. The settlement where they lived was much bigger now. John became a teacher and taught at the one-room school the settlers had built. Sara decided to be a prospector. She had heard stories about people who were finding gold farther north. So Sara bought supplies and one day was ready to leave. She promised John she would write to him. John didn’t

hear from Sara for many months. Then, finally, a letter arrived. In the letter, Sara wrote, “On my way north, I passed through Tree Tops Valley. You would be amazed at how the valley looks now! Our old cabin is still there, but everything else has changed. The whole valley is full of berry bushes. I had a feast!”

(Stop here to let the students draw a picture of this phase of the forest.)

The letter gave John an idea. He thought, “When I have children of my own, I’ll take them berry picking in the valley. That would be fun!” Soon after that, John got married. When his oldest son was 10 years old, he remembered his idea. He took his family to the valley to pick berries. His children loved the valley. But there were not berries to pick. Most of the bushes were gone. Instead, the valley was filling with deciduous trees. John wrote to Sara about them. He wrote, “There are lots of leafy green trees in the valley. And I saw some conifer seedlings. The leafy trees have shaded the berry bushes and choked them out. I don’t know what the trees are called, but they have made the valley all green again.”

(Stop here to let the students draw a picture of this phase of the forest.)

Many years passed. John’s children grew up and had families of their own. One summer, when John was 75 year old, he received a letter from Sara:

Dear John,

Remember how we loved Tree Tops Valley when

we were young? Lastmonth I decided to visit it again,

before I got too old to make the trip. It was a long ride,

but I made it! You would be happy to see our valley

now. It’s beautiful! Remember the leafy green trees you

saw on your last trip there? Well, most of them are gone.

Now the valley is full of young coniferous trees. Who

knows? Maybe our grandchildren will see the valley

looking the way we once saw it.

Love,

Sarah

The years went by. It was now 100 years since the fire had swept through Tree Tops Valley. One day, John’s granddaughter, Jennifer, was looking at some old family letters. She found the letter Sara had written to John after her last visit to Tree Tops Valley. “Look at this,” Jennifer said to her husband. “It’s a letter that belonged to my grandfather, John. His sister wrote it to him. It’s all about a place called Tree Tops Valley. I wonder if we could find the valley. Why don’t we try?” And that’s what they did.

Jennifer and her husband found the valley. They even found the hill where Sara and John had taken their picnics. From the hill they could see tall conifers filling the whole valley. They climbed down and explored and enjoyed the shade of the tall trees. While the trees were tall and mighty, Jennifer and her husband had evidence from the past that the forest would not always be the same. They wondered if someday, they too might witness the changes in Tree Tops Valley that Sara and Jon talked of in their letters.

(Stop here to let the students draw a picture of this phase of the forest.)

348 Project Learning Tree • PreK–8 Activity Guide Activity 80 • Nothing Succeeds Like Succession © American Forest Foundation Student Page