The Copper Basin Problem: Student Section Investigation 5

What Effect Does Fertilizer Have on the Growth of Plants?
(Coordinates with Teacher Lesson 6)

The nitrogen cycle is important for the growth of plants. Our chemical tests of the soil indicated a shortage of nitrogen in the Copper Basin soil. In this experiment we will show that adding fertilizer to the Copper Basin soil could improve its ability to grow plants.

Problem:

How does fertilizer affect the growth of plants in an ecosystem?

Materials:

• small cups
• ruler
• 1/8 teaspoon measures
• nitrogen fertilizer
• grass seeds
• potting soil

Procedure:

1. Construct a table in which to record your observations.
2. Predict the effect of fertilizer on the growth of grass plants.
3. Fill 9 cups with potting soil. Add the same number of grass seeds to each cup (use at least 10 seeds/cup). Label the cups 1 - 9.
4. To cups 1-8, add amounts of fertilizer in increments of 1/8 teaspoon. Do not add fertilizer to cup 9. Place cups in a sunny location.
5. Observe the cups daily and observe any changes in the color of the grass. Measure and record the average height of the plants in each cup.