Youth Education Program of San Francisco Botanical Garden Society

Web of Life

Walk Outline

The lives of all plants and animals are interwoven in a delicate web of life. All living

things depend on each other and their environment for the food and materials they need

to survive. The Web of Life walk introduces children to this complex balance of life by

focusing on ecology – the study of interrelationships between living things and their

environment.

The word “ecology” comes from the Greek work “oikos” meaning home or household.

As children explore the gardens they will be able to visit many different kinds of homes or

habitats – a grassy lawn, pond, a meadow, perhaps a redwood forest or even a desert-

like succulent garden. Use all your senses to observe and describe the differences and

similarities in habitats. On your walk you may see squirrels, pill bugs, butterflies,

dragonflies, birds, turtles, fish, ducks, and more. Incorporate them into your walk and

explore their roles in the web of life. Observe how the members of these ecosystems

interact with and depend on each other. For example, animals need plants for shelter,

building materials and food. In return, plants rely on animals for pollination, seed

dispersal and decomposition.

By studying ecology we can begin to understand the amazing balance of life on our

planet, and to understand how all living things are affected by changes in the

environment.

Concepts:

1. Plants and animals living together in their habitats create a complex web of life.

2. Because they are able to make their own food using the energy of the sun, plants

are the base of all food chains and food webs.

3. In every natural habitat, living things depend on each other in many different ways

for survival.

4. People are part of the web of life and can affect the natural world in positive and

negative ways.

Some suggested materials:

A folder, tape, pen for collecting samples; post-its or sticky labels for making food

chains; a piece of white paper to observe decomposers; magnifying glasses or bug

boxes.

Web of Life Walk Outline

2

Suggested Stops and Concepts – pick 2-4 depending on grade level, your and their

interest, concepts they are working on that you can reinforce, even weather! Also, though

only one or two of the key concepts are highlighted at each stop in this outline,

remember that all four concepts can be woven in at any point on your garden walk.

Meadow

Main Lawn, Exhibition Garden Lawn

WHO LIVES HERE? Look around you, what do you see? Do you think there are any

animals here? Why do you think so? Could any of the things you see survive all alone on

this planet? All of the life you see around you works together to survive and grow. What

are the things we need for survival? What do other living things need? (air, water, food,

shelter, space)

HABITAT/COMMUNITY Ecology comes from a Greek word meaning “home”. What

things do you have in your home to help you live and to make you comfortable? The

home of a plant or animal is its habitat. A habitat is where a living thing finds all of the

things it needs to live. What is a community? You live in a community that helps you get

all of the things you need to live. In your community, different people have different jobs.

All living things have their own communities, and every living thing has a job in the

community. We call these communities “ecosystems”.

PHOTOSYNTHESIS Take a look around - what color do you see all around you? The

green plants around us make the world a place we can live. Take a deep breath. One of

the things we need to live is air. Plants make oxygen, which is part of the air we animals

need to live. Why do plants make oxygen? They don’t make it because we need it –

oxygen is just a leftover when they make their own food! The green part of the plant, the

chlorophyll, uses energy from the sun to turn water, air and nutrients into food for the

plant. If plants didn’t make food for themselves (through photosynthesis) we wouldn’t

have good air to breathe or food to eat

Activities: Be a plant; Share your air

Small Pond

Anelli Ponds, Fragrance Garden Pond

WHO LIVES HERE? Water is the most important thing about this habitat. What do you

think might be living here? In the water? Above the water? Look carefully!

Web of Life Walk Outline

3

FOOD CHAIN A plant uses some of its energy to grow, but it also stores some of this

energy in its roots, leaves, stems, and fruit. We get part of this energy when we eat

plants. No matter what you eat, you become part of a food chain that goes back to the

energy that comes from the sun. What did you eat for breakfast? Can you follow that

food chain back to the sun? Let’s see if we can find some food chains in this pond. What

are some of the living things in this habitat?

Activity: Make a food chain; sense poem; I am a camera

Forest

Mesoamerican Cloud Forest, or Heidelberg Hill/Rhododendron Garden

WHO LIVES HERE? The trees are what make this habitat a forest, but there are many

other living things here. What kinds of animals need trees?

HABITAT How is this area different from the last area you visited? Use all of your senses

to explore this area. Temperature, wind, light, moisture, types of plants.

PLANT/ANIMAL RELATIONSHIPS – POLLINATION Notice the many flowers that grow

here. Many plants need help from animals to move their pollen from one flower to

another, so that they can make new seeds. Red tubular flowers are well-adapted to

attract hummingbirds, who visit the flowers to get nectar and end up with pollen stuck to

their foreheads, while more open flowers with yellow, white and blue parts are especially

attractive to honey bees.

PLANT/ANIMAL RELATIONSHIPS – DECOMPOSITION What happens to a tree when it

dies? It slowly rots away with the help of special animals, plants, and fungi called

decomposers. The bigger decomposers, like pill bugs, worms and snails, break down

larger pieces of dead plants and animals too. Then smaller decomposers including fungi

and bacteria break things down even further. As things decompose, nutrients and other

materials are released back into the air, soil and water. All living things decompose after

they die, and their bodies are broken back down.

Activity: Explore the duff; search for ghost leaves; update food chains with decomposers.

PLANT/ANIMAL RELATIONSHIPS - SEED DISPERSAL Look for different kinds of seeds and

fruits. In order to grow well, seeds have to get somewhere where they have enough

space, water, and sun to grow. Many times animals help the seeds travel. How?

Activity: Draw new relationships between food chain elements.

Duck Pond

Web of Life Walk Outline

4

WHO LIVES HERE? This pond was created by people. Many different animals live in or

visit this pond. What can you see living around the pond?

HUMANS IN THE WEB Since we share the world with all other living things, we have to

understand how our actions affect the environment. Do you think people can live without

being a part of the web of life? What are some things that people do that change the

way other animals and plants live? What are some things that make it harder for plants

and animals to live? What can we do that helps plants and animals live?

Activity: Look for signs of human impact in and around this pond (people feeding birds,

litter, gardening or construction around the pond)

Remember! If the group is really involved in one location or activity, that’s great! Decide

which concepts and ideas you are most comfortable with and focus on them long enough

to convey your enthusiasm and excitement. Reinforce concepts after introducing them

and remember that everything children observe in the garden can be connected.