High School – Focus on Forests – Activity 1, Monitoring Forest Health


Students will conduct a forest health checkup of a local forest area, will take forestry measurements, and will evaluate the ecological services provided by trees and forests.


Biology, Environmental Science, Geography, Mathematics

Time Considerations

Part A—one 50-minute period, plus time in the field (which can vary)


  • Copies of all student pages
  • Area map showing potential study sites (optional)
  • Flag markers
  • Clipboards
  • Tape measures
  • String
  • Colored chalk
  • Spades or trowels
  • Plus paper cups or small plastic bags
  • Distilled water
  • Eyedroppers
  • Petri dishes or plastic containers
  • pH paper (with range of at least 5–10)
  • White paper
  • Compass
  • Overhead transparency sheet  


A forest is a complex system with many interdependent elements, including plant and animal species, soil and water, and cycles and processes. When it is functioning well, this system supports a diversity of species, helps to store and filter water, improves air quality, stores carbon, and performs other vital ecosystem services. People depend on healthy forests for these ecosystem services, as well as for wood and other products.

Foresters measure forest health in a number of different ways. Assessments may include the number of acres of forestland, the rates of growth of trees, the condition and diversity of plants, and the animal species supported by the forest ecosystem. Because measuring the many components of forest ecosystems for every forest would be impractical, forest health monitoring focuses instead on specific indicators of forest health.

In this activity, students will examine vital sign indicators that provide a checkup on forest health. Students will also evaluate some of the ecosystem services provided by healthy trees and forests.

Activity Instructions

Part A—Forest Health Checkup

  1. Ask students the following questions: “What do you think forest health means? Why should we care whether forests are healthy or not? What factors do you think might promote or diminish forest health?”
  2. Explain to students that they are going to study a local forest to look for indications of its health. Point out that just as a doctor takes the temperature and measures blood pressure to assess a patient’s general health, foresters use specific vital signs to assess forest health.
  3. Ask students what sorts of things might indicate that the forest is healthy, and list their ideas on the board. Ask them what things might indicate poor health, and add those ideas to the list. Give students copies of the “Forest Health Indicator” student pages, and discuss the indicators included. How do the indicators compare with the list generated by the class? Is there anything from the class list that should be added as an indicator? How would that indicator be investigated? Are there any indicators that would not make sense for your forest
  4. Describe the site(s) you have researched (see Getting Ready). You might point out each location on a map. If students will be selecting the forest area to study, have them discuss the pros and cons of each site and then vote for the forest they want to study.
  5. Explain that the class will mark off a 0.1-acre study plot (or several plots), within which the class teams will conduct one or more of the investigations. You may choose to let each team have its own plot for doing all the investigations, or you may have one plot to study as a class, with different teams doing different investigations. In either case, have at least two teams do each investigation to increase data validity.
  6. At the study site, decide whether the plot(s) should be circular or square, depending on the terrain. Have students mark the boundaries of each 0.1-acre plot (4,356 square feet, or 405 square meters) as follows:
    A pair of students measures and marks their forest plot with a small orange flag.
    Students measure and flag their study plot.

    • For a circular plot, have students place a flag in the ground to denote the center of the plot. Then, have them use a 50-foot tape measure to measure 37.2 feet (11.34 meters) from the center.
      They should make a circle around the center marker with the outstretched tape and should place flags to mark the
      circumference of the circle.
    • For a square plot, have students measure a square with sides 66 feet (20 meters) long. It may help to stretch two strings diagonally from corner to corner (the strings should be 93 feet, or 28.3 meters, long) to establish the plot’s boundaries, plot center, and corners. Have students flag the plot boundaries.
  7. Divide the class into teams to perform the investigations. You might have groups mark trees with chalk (with a different color for each group) to indicate which trees were sampled.
  8. Give each student a copy of the “Forest Health Summary” student page to complete. If all the teams conducted each of the investigations, have the teams tally their results on that page. If different teams conducted different investigations, have the teams share their results. Give teams sufficient time to reach a conclusion about the overall health of the forest plot.
  9. Discuss the following questions:
    • What was your assessment of the overall health of the forest plot?
    • Which results were the most important in making your assessment?
    • Do you think the results are representative of the entire forested area? Why or why not? How might a more accurate assessment be obtained?
    • How do human activities either degrade or enhance the health of this forest?
    • What could people do to improve it?

To review the remainder of this lesson, including Part B—Ecosystem Services, activity enrichment, printable student pages, and assessment opportunities, download the full activity.

Get the complete guide.

  • Integrate teaching about forests into a multitude of subjects
  • Lesson plans include hands-on classroom studies and outdoor field investigations
  • Nine activities help students develop critical thinking skills and debate real-world decisions focusing on forests

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