Muir Woods Nature Detectives

Welcome to Muir Woods National Monument! The ancient coast redwood forest is a place full of mysteries to investigate. There are four different investigations you can do to learn about the redwood forest. Choose what you would like to do from the links below.

When a Tree Falls in the Forest

pacific wren

How is a fallen tree a part of the forest? In this scenario you will investigate how different forms of life in the redwood forests depend on dead trees. Find as many different creatures hiding in the forest as you can. Each creature you find is recorded in your notebook. After your exploration build an interdependence web using the different organisms you’ve discovered and see how connected dead trees are to the forest community.

Grades 3/4

Play When a Tree Falls in the Forest

Plant Invasion

french broom

Muir Woods is being overrun by invasive plants! These plants don’t belong in the forest and threaten to take over the native plants that many animals require for their habitat. As a nature detective use your field guide to determine which plants belong in the redwood forest. Remove the invasive plants that have started growing and watch forest animals return.

Grades 3/4

Play Plant Invasion

Crustacean Frustration


How does competition affect a food chain? Fish biologists have found that invasive crayfish have been eating the endangered young coho salmon that live in Redwood Creek. Should the park rangers remove the crayfish? As a nature detective, your task is to investigate 2 sections of the watershed – one area with crayfish and one without. Compare your findings of the two areas and decide if the crustaceans should be removed.

Grades 4/5

Play Crustacean Frustation

What Needs Fog?

redwood snail

How do members of the forest community depend on fog? Scientists have recently discovered that the amount of fog in the redwood forest is decreasing. In this scenario you will explore 2 different areas in the forest – one with fog and one without. As a nature detective you will investigate how each part of the forest uses fog and show the relationships in an interdependence web.

Grades 4/5

Play What Needs Fog?