III.A.2 DECOMPOSING THE DECOMPOSERS:
Mushrooms and their Associates

Concepts: Insect/fungal associations, decomposition, food web, and classification.
Skills: Observation, cooperative learning, data recording and interpretation, and description.
Time needed: Part One: approximately 10 minutes each day. Part Two: approximately 15 minutes.
Best time of year: Anytime of year that mushrooms are present (wet periods).
Sunshine State Standards: LA.B.2.2.1, LA.B.2.2.6, MA.E.1.2.1, MA.E1.2.3, MA.E.3.2.2, SC.G.1.2.1, SC.G.1.2.2, SC.G.1.2.4, SC.G.2.2.1, SC.G.2.2.2, SC.G.2.2.3.



This classroom activity has 2 parts. During Part One, students will observe how a mushroom changes over a two to three week period and will record their observations. In Part Two, students will analyze data the class collected.

III.A.2 Part One-Collecting the Data


Materials:

Each team of 2 students needs:

  • One mushroom with collection label
  • Plastic wrap to fit over jars
  • Rubberbands (one for each jar)
  • Cotton
  • Black construction paper (one sheet per jar)
  • Scissors
  • Tape
  • Decomposing the Decomposers data sheet
  • Pencil
  • Clipboard
  • Hand lens or magnifying glass
  • Small vials or jars

Teacher needs:

  • Clean, clear glass or plastic bottles (mayonnaise, peanut butter, or pickle jar). One jar for each team.
  • Dry, sifted sand (enough for 2-3 inches in each jar)
  • Funnel (can be easily made with paper)
Instructions for the teacher:
  1. Each team of 2 students needs a mushroom to observe. Use mushrooms collected from the previous activity, Mushrooms-What Are They Good For, and/or mushrooms you bring from home. Make sure a collection label is included with each mushroom.

  2. Prep the jars with the 2-3 inches of sand. (You may choose to go ahead and put the mushrooms in the jars and tape the collection label to the outside of the jar.)

  3. Distribute materials to your teams of students. Instruct students to cover the jar with clear plastic wrap once the mushroom is inside and secure the plastic with a rubberband.

  4. Instruct students to make a small hole in the plastic wrap with the sharpened end of a pencil and plug the hole with a wad of cotton. Be sure the cotton is secure and won't fall into the jar.

  5. Have students tape a piece of black construction paper around the jar so that the sand is covered, but the mushroom is still visible. (This mimics the darkness underground.)

  6. Write a number on each jar and make sure each team knows the number of its jar.

  7. Place the jars in a low traffic area of the classroom, but where students can still easily observe the mushrooms. Each day, the students should carefully observe the jars and record information on their data sheets. Water droplets may collect in the beginning, but the sand will absorb most of it. After a day or so, mold may begin to grow.

  8. Once mold begins to form, have a brief mold discussion with your class. Explain that mold is also a fungus and the white threads of the mold are hyphae, similar to mushroom hyphae.

  9. Keep a sharp lookout for insect larvae tunnels that may be visible close to the edge of the glass (You may lift the black paper for viewing.) If students look carefully, they might see the tiny larvae or pupae of insects that were most likely in the egg stage when the mushroom was collected.

  10. Watch the jar for several weeks and record data. Be careful to look in all parts of the bottle-but without disturbing the sand. The young insects will mature into adults and can be seen flying under the plastic wrap. To more closely view the insects, remove the cotton wad and place a small vial over the hole. The natural tendency of most insects is to fly up to higher, brighter areas, so they will fly into a well-placed vial. Replace the cotton and examine the insect(s) with a magnifying glass-or with a dissection scope if you have access to one. (Illustrations of insects commonly found in and around mushrooms.)

  11. When recording the insects your students find, it is not important that they correctly identify them. However, the students should be able to describe what the insects look like and be consistent with their description when recording data. Encourage your students to create look-alike categories. For example, if a student identifies an insect as a spotted wing fly one day, the same description must be used each time the student sees that kind of insect.

  12. On the last day of the activity, discuss how conditions may differ between the mushroom in the jar and an outdoor mushroom that has fallen on the ground.
    • More moisture will be visible indoors because sunlight and wind would dry out the mushroom on the ground.
    • Because air does not circulate freely around the mushroom in the jar, it stays very moist and the mold can grow more rapidly for a longer period of time.
    • The mushroom in the jar is protected from predators such as mice and squirrels.
III.A.2    Part 2    Student Data Sheet
III. LIFE IN THE LEAF LITTER LAYER
A. Mushrooms:    III.A.1    III.A.2    III.A.3
B. Life in a Microhabitat    III.B.1
C. Glossary    D. Questions for Student Evaluation