Smithsonian National Zoological Park l Friends of the National Zoo



Is There Life in a Decomposing Log?

4. Outside Explorations

children turning over nad investigating a log children in a group finding species in a decaying log children in a group getting data

In this activity, you will go outside to explore a rotting log habitat and learn about forest ecosystems, life cycles, and relationships among species.

By observing the types of species found in a rotting log, and by documenting your observations, you will also learn science skills such as how to collect, organize, and analyze scientific data, and you will use math skills, including measuring, graphing, and calculating.

We recommend that you work in a small team of 2-5 students. Your teacher will assign each team a log to investigate.

If decomposing logs can’t be found, or if the weather is bad, bring a rotting log into your classroom to investigate, or substitute a tray of leaf litter.

Your teacher will give each team a student worksheet, "Decomposing Log Data," as well two handouts "Stages and Characteristics of Log Decay" and "Common Species Found on Decomposing Logs."

Before going outside, make sure you have the following:


  • Clipboards
  • Metric rulers or measuring tapes
  • Pencils (Optional: colored pencils )
  • Hand-held magnifying lenses
  • Optional: Microscope for closer observation

Use good teamwork to explore your log, and record your observations. It may help to assign tasks to each person before going outside.

Follow the instructions on the student worksheet “Decomposing Log Data” to document the characteristics of your decomposing log and collect data on the species you find.