Curved Tree Trunks

Many of the trees surrounding the oxbows at Chichaqua Bottoms Greenbelt seem to be curving up and away from the water, while the tree trunks on land tend to be more straight. The trees that are growing along the oxbow bank follow the sunlight as they grow, causing them to curve toward the sky.

• Why are the trees near the water growing in such a funny way?

• What do trees need to grow?
• How could we find out what trees and plants need to grow?

Students could:

• Recall plants they may have growing around their home; discuss what they think plants need to survive.
• Conduct an experiment planting some plants in light and other plants in the dark, some plants with more water and other plants with less water.
• Measure the plants daily and write down observations.
• Compare the results of plants with various amounts of water and light to determine what plants need to grow.
• Read the book “Oh Say Can You Seed” by Bonnie Worth.
• Model the parts of a plant by matching plant part names (roots, stem, leaves, flower) to their location on a picture.
• Observe teacher demonstration of placing celery in different colors of water to show how plants receive water.
• Create a plant maze as a class to observe how the plant grows toward the light.

• TeachEngineering | What Do Plants Need?: This demonstrates an experiment where levels of light and water are adjusted to see the impact on the growth of the plant.
• Science Sauce | Phototropism Explained: This video provides a background for the teacher of why plants grow towards the light.
• SciShow Kids | The Color-Changing Celery Experiment: This video demonstrates colored water traveling through celery.