Habitats - Rotting Logs

Focus: A rotting log serves as a habitat for many plants and animals, which vary according to the log's stage of decomposition.

Puppets (Rocky Raccoon, Benjy Bear, Charlotte Spider, Wendy Worm)

Materials Checklist
Time Machine (four small logs in various stages of decay, time machine – decorated cardboard box, optional professor's costume)
Puppet show (puppets, script, real or constructed rotting log, a card with the word 'directions' on it taped to a stick)
Log Look (rotting logs, one for every four children, hand lenses, paper, pencils, flashlights, bug boxes or white dishpans, optional plastic tarps or newspaper, optional field guides)
Bark Beetle Investigation (bark beetle engraving samples, hand lenses, pencil and paper, Engraver Beetle story, optional polymer clay, spalted wood)

Supplementary Reference Materials (Bark Beetle Diagram, Rotting Log Critters, Critter Information, Time Machine Gauges, Crossword Puzzle). You can also use this Fungi reference sheet: Fungi on Rotting Wood (pdf file) or read about Spalted Wood (pdf file).

Additional Reading/Resources
Dead Log Alive!, by Jo Kittinger, Scholastic Press, 1996.
Website on wood-decaying fungi.

Teaching suggestions

Time Machine
If the box is big enough, it can be operated by the professor from the front. Place the door 6" or so from the bottom of the box. Hinge it on the bottom, so it opens out without revealing what's inside. Place all stages inside so the professor just switches the different stages.

A young seedling planted in the final rot stage is nice to show the full circle.

Note: "punky" actually describes wood that is dry and crumbly!

Professor's names: Dr. Otto Lot, Professora Decomposta, Maestro Gustavo Orthotomicus (but my friends call me Fun Gus)

Remember to keep the time machine to use in Litterbugs.

Log Look
If it's very cold outside, bring in large log pieces (on plastic sleds) a few hours ahead of time. Let students know that you will be returning these to the place where they were collected.

Bring in other examples of early stages of decay: branch with sapsucker holes, other beetle tracks, shelf fungus.

Stokes' Nature in Winter has a chapter on shelf and other fungi ("Winter Mushrooms"). Look for slug eggs – 1/8", pearly spheres!

Bark Beetle Investigation
Though in the activity extensions we suggest creating medallions of beetle tracks with polymer clay, people have expressed some concern about the safety of this material. You might want to do bark track rubbings instead placing paper over log and rubbing with side of peeled crayon.

Order of Activities
You might want to change the order of the activities to do Bark Beetle Story before Log Look.

Learning Goals

Concepts/Ideas:

• A rotting log on the forest floor plays an important role in the forest ecosystem providing an ever-changing habitat for a variety of creatures big, small, and microscopic
• As a log decays it passes through a series of stages as it progresses from a tree to soil. During each stage the log is home to a community of plants, animals and other organisms.
• Bark Beetles are organisms that help start the process of decay in a dead tree.

Vocabulary: Habitat, Decomposers, Decomposition, Stages of Decomposition, Forest Ecosystem, Community, Frass, Humus, Fungi, Spores, Hyphae,

Skills:

• Active listening to learn about the stages of a log's decomposition and to learn that a rotting log can provide a home for many different animals
• Exploring and examining a rotting log using light, a probe and hand lens.
• Recording and identifying organisms found in a rotting log using diagrams and field guides.
• Examining patterns on a section of log and hypothesizing ideas about how the patterns were created to learn the story they tell about an insect's life cycle.

Grade Expectations:
Grades PK-K (S30, S38) A rotting log is “home” for a variety of animals and plants. Plants and animals that live in a rotting log need water, food and air to live. Bark beetles are one kind of animal that lives in decaying logs.

Grades 1-2 (S30, S31, S36) A rotting log provides food, shelter and space for a variety of animals and plants. Some animals and plants depend on decaying materials and dead organisms for food. Bark beetles use decaying wood as habitat and undergo developmental life stages under tree bark.

Grades 3-4 (S30, S31, S36) A rotting log serves as habitat for plants and animals whose needs are met there. Plants and animals that live in/on a rotting log interact in various ways in addition to providing/obtaining food. Bark beetles have physical and behavioral characteristics that help them to live and grow in decaying logs.

Grades 5-6 (S30, S34-S37) Many of the inhabitants of a rotting log are decomposers; organisms that use waste material and dead organisms for food. Organisms that live in, on or near rotting logs engage in interdependent relationships as they acquire their food to meet energy needs.

Return to November ELF