Colorado Reader Feb. 2020: Soil, Water, and Air Stewardship | Page 10

olorado
Reader
Student Activity
Soil, Water, and Air Stewardship
Science Experiment - Erosion Model
In this experiment, you will observe how plant life
and ground cover minimize soil erosion.
Go to https://www.youtube.com/
watch?v=im4HVXMGI68 to watch this
experiment.
Materials:
• 1 x piece of ply wood (30cm x 30cm x 2cm thick)
• 6 empty 2 liter bottles
• Scissors and/or Stanley knife
• Wood glue
• Hole puncher
• String
• Bag of soil
• Mulch (bark chips, dead leaves and sticks)
• Grass seed or flowers
• Watering can
• Water
Procedure:
1. Prepare three of the bottles by cutting a rectangular opening out of the side of the bottles so
they looks like planters.
2. Stick the bottles to the wood with wood glue, making sure the necks of the 3 bottles hang
evenly over the edge of the board.
3. Fill each of the three bottles about half way with soil.
4. Do not add anything on top of the soil in the first bottle. In the middle bottle, cover the soil with
mulch or dead leaves. In the third bottle, either plant grass (do this 2-3 weeks ahead of time)
or flowers. If you are planting flowers, plant them tightly together and press down firmly to
compact the soil.
5. Cut the other three bottles in half horizontally. Keep the bottom halves to use as collection
bowls. Make holes with the hole punch on each side of the bottle, near where it was cut. Cut
three identical pieces of string, roughly 10 inches long. Thread a piece of string through the
holes and tie knots at each end to secure the string. Hang the string and bottle over the necks of
the three bottles that are being used as planters.
6. Finally, make it rain! Slowly pour equal amounts of water in each of the planter bottles using the
watering can. Pour the water in at the end furthest from the neck of the bottle to simulate rain
moving through the soil. Observe the color of the water collecting in the bowls. You can add
water to the bottles every day and see what happens to the soil over a period of a week.
Questions to answer:
1. What do you observe in each of the collection bowls?
2. Why do you think they are different from each other?
3. How do plants and ground cover help minimize erosion?
4. How does this experiment apply to farming? Based on this experiment, how are farmers helping
soil health?