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Reading passage Grade 6 English Language Arts

Two Sides of Fertilizer at Harlow Lake: A Grade 6 Reading Passage

A grade 6 informational passage about how the same nutrients that help a fictional farm's crops can harm a nearby lake, with comprehension questions.

Objectives

  1. Students will trace how nutrients travel from a farm field to a lake.
  2. Students will explain why the same nutrient can be a resource or a pollutant.

Vocabulary

Key words: nutrient, fertilizer, runoff, algae bloom, oxygen

Teacher overview

This passage builds one clear central idea: the same nutrient can be helpful in one place and harmful in another. Using a fictional farm and lake, it traces nitrogen and phosphorus from a fertilized field into Harlow Lake and shows the chain of effects an algae bloom sets off. The passage is a strong text for teaching how an author presents two sides of a single topic. The questions ask students to trace the cause-and-effect chain and to state the central idea in their own words.

Two Sides of Fertilizer at Harlow Lake: A Grade 6 Reading Passage — Grade 6 English Language Arts
Name: ____________________________ Date: ______________

Passage

Nutrients are a kind of food for plants. Two important ones are nitrogen and phosphorus. Plants need these nutrients to grow leaves, stems, and seeds. Without them, a field of crops would grow slowly and stay small.

On the fictional Meadowbrook farm, the soil does not have enough of these nutrients on its own. So the farmers add fertilizer. Fertilizer is a material rich in nitrogen and phosphorus. With it, the farm's corn grows tall and green. Here, the nutrients are a resource. They help the farm feed people.

Rain changes the story. When a heavy rain falls, some fertilizer does not stay on the field. Water runs across the ground and carries the extra nutrients away. This moving water is called runoff. The runoff flows into small streams. Those streams flow into Harlow Lake, which sits at the bottom of the valley.

In the lake, the same nutrients act in a new way. They feed algae. Algae are tiny living things that float in the water, a little like plants. When extra nutrients arrive, algae grow very fast. Soon a thick green layer covers the surface. This fast growth is called an algae bloom.

The bloom starts a chain of problems. The green layer blocks sunlight from reaching deeper water. In time, the algae die. As they rot, they use up oxygen in the water. Fish and other animals need that oxygen to live. When the oxygen drops too low, fish can grow sick or die. Here, the same nutrients that helped the corn have become a pollutant.

So one nutrient can be a resource or a pollutant. What makes the difference is where it ends up. On the field, nitrogen and phosphorus help crops. In the lake, they feed a harmful bloom.

Farmers and towns work to keep nutrients on the field. Farmers can test the soil first and add only as much fertilizer as the crop needs. They can plant strips of thick grass between the fields and the streams. These grass strips catch runoff and soak up nutrients before the water reaches the lake. Small changes on the farm can keep Harlow Lake clear.

Questions

  1. What are the two nutrients named in the passage?
  2. Why do the farmers at Meadowbrook add fertilizer to their fields?
  3. What is runoff, according to the passage?
  4. How do nutrients from the farm reach Harlow Lake? Describe the path.
  5. What happens in the lake after extra nutrients arrive? Describe the chain of events.
  6. The passage says the same nutrient can be helpful or harmful. Explain what makes the difference.
  7. Name one way farmers try to keep nutrients on the field, and explain how it helps the lake.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: Nitrogen and phosphorus, the two nutrients the passage names.
  2. Answer: Because the soil does not have enough nitrogen and phosphorus on its own, so fertilizer helps the corn grow tall and green.
  3. Answer: Runoff is water that runs across the ground during rain and carries the extra nutrients away from the field.
  4. Answer: Rain runoff carries nutrients off the field into small streams, and those streams flow into Harlow Lake at the bottom of the valley.
  5. Answer: The nutrients feed algae, which grow fast into a bloom, block sunlight, then die and rot, using up oxygen so fish can grow sick or die.
  6. Answer: Answers will vary but should say the difference is where the nutrient ends up: on the field it helps crops, while in the lake it feeds a harmful bloom.
  7. Answer: Answers will vary. Students may name testing soil and adding only what the crop needs, or planting grass strips that catch runoff, and explain that this keeps nutrients out of the lake.

Differentiation

Support

Provide a five-box cause-and-effect chain (extra nutrients, fast algae growth, blocked sunlight, algae die and rot, oxygen drops) for students to fill in from the passage before answering item 5.

Extension

Ask students to write a short paragraph explaining the central idea to a younger student, using the words "resource" and "pollutant" and one example of each from the passage.

ELL supports

Pre-teach "nutrient," "fertilizer," "runoff," and "algae bloom" with a picture for each, and allow students to answer items 1 through 4 with short phrases or by ordering picture cards of the chain.