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Grow It 3-5 / Week 10 / Wednesday
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Week 10 · The Garden Food Web

Wednesday

The clean-up crew
// Who eats what, and where it all goes
⏱ about 15 min

Wednesday: The Clean-Up Crew

Rocket rakes a big pile of fallen leaves. "Where do all the old leaves go?" he asks. "The garden would be buried!"

Raven lifts the bottom leaves with a gloved hand. They are soft, dark and crumbly. "What do you notice down here?"

An earthworm wiggles away. Nova hovers low. "Check your compost bottle too," she says.

Decomposers

Decomposers break down dead plants and animals.

Earthworms, fungi and bacteria are decomposers. Roly polies help too.

They turn old leaves into nutrients that new plants can use.

A teaspoon of rich soil can hold 100 million to 1 billion bacteria!

Without decomposers, dead leaves would pile up and up.

Earthworms at work

Earthworms tunnel through the soil and feed on dead plant matter.

Their tunnels let air and water move into the soil.

Worms leave droppings called casts. Casts hold nutrients that plants need.

Some worms come up at night to feed on leaves. In the heat of the day, they stay deep.

DECOMPOSER OR NOT?
  • Read the question.
  • Tap your answer.
A fungus grows on an old log and breaks it down. What is it?
What do earthworm casts give to the soil?
When do some earthworms come up to feed on leaves?
Worms, fungi and bacteria are ____.
Worm droppings are called ____.
Try it
Look at your compost bottle from last week.
Compare it with your notes. What looks different?
Look for darker bits, smaller pieces or mold.
Safety first
Keep the compost bottle closed. Look through the sides only.
Wear gloves if you touch soil or leaves. Wash your hands after.
Never smell, taste or touch mold.
FROM FALLEN LEAF TO NEW FOOD
  • ?Plant roots take in the nutrients.
  • ?Nutrients go into the soil.
  • ?Worms and fungi break it down.
  • ?A leaf falls to the ground.
WHY THIS EXERCISEDecomposers recycle old leaves into food for new plants.
StatementTrue or false?
Decomposers break down dead plants and animals.?
Earthworm tunnels let air and water into the soil.?
Bacteria are too few to matter in soil.?
Fallen leaves stay whole forever.?
WHY THIS EXERCISEDecomposers are everywhere in soil, breaking down old leaves.
Name one decomposer that lives in garden soil. Type one word.
WHY THIS EXERCISEWorms, fungi and bacteria are decomposers.

Check your bean plant. Measure its height and count its leaves.

Does your bean plant need any decomposers in its pot? Think about it.

Wonderful work, clean-up crew! Tomorrow we link everyone together into a food web.

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