FOCUS: Under a canopy of trees, the forest floor is a cool, damp, and protected environment. Here in the leaf litter millions of small organisms – fungi and bacteria, springtails and mites, spiders and centipedes and others – are all part of a rich food web. Many of these are decomposers, feeding on plant and animal remains and turning them back into soil.
Objective: To begin to explore and ask questions about leaf litter.
Pour a garbage bag of full of freshly fallen leaves onto a sheet. Point out that these are just some of the leaves that fall from a single tree, each year. Ask children, “With so many leaves falling in a forest every year, why aren’t they piled up high in the forest?”
Materials: a garbage bag full of freshly fallen leaves, old sheet.
EFT’S EYE VIEW
Objective: To experience the world as it might seem to a small creature living on the forest floor.
Be sure to check for poison ivy first. Have children lie on the forest, facing upwards. What do they notice about their surroundings, such as the amount of light on the forest floor (shady), amount of wind (little), noise (quiet), moisture (damp), fragrance (musty, moldy, like damp earth). Have children roll over onto their stomachs and find a place to dig a little nose hole in the leaf litter; take a sniff of the good smell that tells us decomposition is underway.
In what ways is the forest floor different from other habitats such as an open field, the treetops, a desert? (Less sunlight, damper, less windy.) Why would this be true? (Trees block the wind, filter the sun, hold in moisture.)
LAYER BY LAYER PROFILES
Objective: To explore a section of forest floor, making a model of the different layers and looking for evidence of decomposition and decomposers.
In small groups, have children explore a section of the forest floor, looking for evidence of decomposition, decomposers, and other items listed on the Leaf Litter Search card as they go down through the layers. Give each team a piece of cardboard or a white dish basin on which to build their leaf litter profiles. Each group uses a three-foot length of string to encircle a section of leaf litter to explore. Have them pick one or two items (but not living plants or animals) from each layer to stick onto their cardboard, as they work their way down through the leaf litter to the soil. Have them carefully collect any animals they find in jars for later examination and keep them out of the sun. Afterward, in small groups, have teams hold up their leaf litter profiles, share any exciting discoveries, and answer the following questions:
- What patterns do they notice as they go down through the layers of leaf litter? (Smaller fragments, darker color, damper, etc.)
- How did the bottom layer of your soil get this way? (By decomposers breaking down the leaf litter.)
- Why is decomposition important for the forest? (Makes soil; reduces build-up of litter.)
Pass around jars for all to see and look for these animals on the Soil, Litter, and Log Critter guide. When done, have children put any living organisms they collected back where they found them and gently replace any rocks or logs.
Look for leaves in different stages of decay:
- freshly fallen leaf
- brown, dry leaf
- skeletonized leaf
- bits of slimy brown rotting leaves
Look for nuts and seeds. How are they important?
Look for tree seedlings. Why are they important?
Look for roots and rootlets.
Look for white fuzzy coating or threads (fungal hyphae) on things like twigs, leaves, bark pieces, roots. Why are they white?
Materials: for each group: Leaf Litter Search card, 3′ length of white string; white dish basin or piece of cardboard; a few clear jars with lids, Soil, Litter, and Log Critter guide, magnifying lens; optional: Critter Information sheet.
Objective: To record observations about something discovered in the leaf litter.
Have children make a drawing in their journals of one favorite thing they found in the leaf litter. It could be a decaying leaf or an animal that was collected in a jar. Have them record as many details as possible about the appearance and behavior of the creature (if they choose an animal). What part might it play in the forest floor ecosystem? If possible, try to count the number of legs on the animal and then compare to the Soil, Litter, and Log Critter guide. Try to identify the group to which the animal belongs. Afterward, as a group, return any critters to the forest floor, using the release poem below. Have children share their journal entries in small groups.
I looked at you,
You looked at me.
I’m glad we met,
And now you’re free.
Materials: science journals or clipboards and paper, pencils, litter profiles and creatures in clear jars with lids from previous activity, Soil, Litter, and Log Critter guide; optional: colored pencils.
Objective: To look for patterns of similarities and differences among some of the very small animals that live in leaf litter and sort into groups that share characteristics.
In small groups, have children look at a set of Litter Critter cards, noting number of legs, presence of antennae and eyes, and other distinguishing features. Ask for ideas of different ways that you could sort these creatures (number of body parts, number of legs, with or without eyes, etc.) Have the children sort them into four groups by the number of legs: no legs, six legs, eight legs, more than eight legs. Afterward, have an adult read the clues below and have the children point to the card (younger children) or call out the name of the animal they think matches the description.
This critter has many legs. Its body looks like a long tube made of rings, with at least two pairs of legs on each ring. Which one is it? (Millipede.)
This critter has no legs. It is fattest in the middle of its body, and it has feelers on its head. On its back it has a hard shell. Which one is it? (Snail.)
This critter has six legs. It has very short wings on its back. At its tail end it has two long, sharp, curved pincers. Which one is it? (Earwig.)
This critter has eight legs. It has a small round body and its legs are very long and skinny. Which one is it? (Daddy longlegs.)
This critter has many legs. Its body is long and thin and it has one pair of legs on each body ring. It twists its body side to side like a snake. Which one is it? (Centipede.)
This critter has no legs. Its body is like a long tube made of many rings. It has no eyes or antennae but it has a band near one end. (Earthworm.)
This critter has fourteen legs, two antennae, and a body shaped like a turtle’s shell. Which one is it? (Isopod.)
This critter has – no wait! It just disappeared! Oh, there it is again. It is tiny and has six legs and a tail folded under its belly that it uses to jump. Which one is it? (Springtail.)
Take the children outside to look for critters in the leaf litter. How many of these different kinds can they find?
Materials: for each small group: a set of Litter Critter cards.
Objective: To design and build small houses for imaginary people using natural materials from the forest floor.
Have children work in pairs or small groups to build a home for an imaginary clothespin-sized person, using materials they find on the forest floor such as bark, twigs, cones, and leaves. Ask them not to disturb living things like mosses, ferns, or animals. Encourage children to use their imaginations as they create their houses. Allow time for groups to take turns visiting other teams’ “elf houses” and explaining their designs.
Materials: any natural materials found on the forest floor, but nothing living.
WHAT’S IN THE BAG? and CAST A LEAF SPELL – Grades K-3
Objective: To notice different kinds of leaf and tree litter that settle on the forest floor.
In small groups, have children work with an adult to explore a section of the forest floor. Pick one item (not a live animal or plant) to hide in a bag for others to guess.
With the whole group, form a circle and pass one of the “guessing bags” about one-third of the way around the circle, allowing children to feel the item and share two or three words describing it. Have the other children try to identify the item from the description. Repeat until all children have had a chance to feel and describe an object.
Now cast a spell. Have each child pick up a dead leaf or hold one of the items from the guessing bags. Have them repeat these magic words, and then toss their dead leaf or other object onto the forest floor:
Abracadabra, fiddledee foil
Make this leaf litter turn into soil!
Why might this spell seem to work? (Decomposers eventually do turn everything into soil, and rocks eventually erode into soil.)
Materials: for each group: cloth or paper bag or pillowcase.
PUPPET SHOW “Litter Critter Jig”
Objective: To meet some inhabitants of the leaf litter and learn how they contribute to the process of decomposition on the forest floor.
Perform the puppet show or have a group of children perform it for the class. Afterward, ask questions to review the key ideas and vocabulary in the play. What important process happens in the leaf litter? (Decomposition.) What does decomposition mean? (Breaking dead things down into tiny bits.) Why are millipedes and worms called “decomposers”? (They feed on dead leaves.) How does a fungus get its nourishment, and is it a decomposer? (Yes. The fungal threads ooze out chemicals that break down dead wood.) What did the springtail eat? (Fungi.) Which characters are forest floor carnivores? (Eft and woodcock.) What is an example of a food chain in the puppet show? (Dead leaf – millipede – woodcock; dead leaf – fungi – springtail – eft.) Hold up puppets as the children name each food chain.
Materials: puppets, script, stage.
UPPER GRADES CHALLENGE: Leaf Litter Bulletin Board (Grades 5-6)
Objective: To create a bulletin board model about the food web in the leaf litter.
While investigating the leaf litter, have each student or pair of students select an interesting animal, plant, fungi, or other item to study further. Have them photograph their selections and try to identify them using the Soil, Litter, and Log Critter guide or field guides and read about them in the Soil, Litter, and Log Critter Information sheet. Students could work with a leader to create a bulletin board display about the leaf litter to share with the school community. Have their display show the different layers of leaf litter, with photos and information about the organisms they found and, where possible, the role each one plays (decomposer, herbivore, carnivore) in the forest floor food web.
Materials: clear jars with lids, Soil, Litter, and Log Critter guide and, Critter Information sheet, white cardboard for photo backdrop, cell phone or camera(s), computer, printer, thumbtacks, craft paper, scissors; optional: field guides.
Objective: To review and reflect on leaf litter discoveries.
Have everyone pick up a favorite fallen leaf and ask them to write about or draw their favorite leaf litter discovery. One by one, have the children toss their leaves onto a pile and complete the sentence: “My favorite leaf litter discovery today was __________ because __________.”
Materials: fallen leaves; optional: clipboards and paper, pencils.