Muir Woods Nature Detectives

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Acorns Acorns are nuts made by oak trees. There are many different kinds of oak trees, so acorns come in many different sizes and shapes. Acorns are an important food for many forest animals like chipmunks, squirrels, deer and woodpeckers. Coast Miwok Indians also collected acorns to make into food. What might happen to the forest community if the acorns disappeared? Acorns - click to see larger picture
Cow Parsnip Cow parsnip has very large leaves. The leaves are food for some animals, like the banana slug. The seeds are also food for other animals, like the chipmunks. Can you think of a way that chipmunks out collecting seeds are helping the cow parsnip plant? Cow Parsnip - click to see larger picture
Elk Clover Elk Clover has a large leaf. It grows near the creek and other wet areas. Deer eat its leaves and its flowers attract butterflies. Why would a plant in the redwood forest grow such large leaves? Elk Clover - click to see larger picture
Leopard Lily The leopard lily is a plant that grows along the creek in Muir Woods. It has very colorful flowers that attract Anna's hummingbirds, bees and butterflies. Park visitors like to pick the flowers. How might this affect the other members of the forest community? What ideas do you have for protecting the flower? Leopard Lily - click to see larger picture
Miner's lettuce Miner's Lettuce starts to grow after the spring rains stop. It is food for many forest creatures, like chipmunks, deer, squirrels, slugs, deer, and mice. California gold miners used to eat this plant, which is where it gets its name. Miners Lettuce - click to see larger picture
Moss Moss grows in the shady and wet parts of the forest. It grows on tree trunks, rocks and fences. Because it is so moist other plants can grow their roots into the moss. Moss - click to see larger picture
Polypod fern This plant doesn't grow in soil - it grows on other plants, like moss. When a plant grows on another plant it is called an epiphyte. The polypod ferns of Muir Woods are found growing into the moss on trees and rocks. How might growing roots into moss help the polypod fern? Polypod Fern - click to see larger picture
Redwood Sorrel Redwood sorrel is the delicate plant that carpets the floor of the redwood forest. Many people call it 'clover' but it isn't. Many animals eat redwood sorrel, like black-tailed deer. Park visitors should stay on the paths so they don't destroy the plant. Redwood Sorrel - click to see larger picture
Solomon's Seal This plant grows close to the ground in the shady parts of the redwood forest. It is a good place to hide for animals that spend a lot of time on the ground. Solomon Seal - click to see larger picture
Sticky Monkey Flower The Sticky Monkey flower grows in sunny spots at the edge of the forest. It is also found in the forest where there is plenty of sun. Its leaves are sticky. The flowers are orange and look like a trumpet. Bees and hummingbirds love the flowers. Sticky Monkey Flower - click to see larger picture
Tanoak The tanoak tree makes acorn nuts, which are food for animals. This makes the tree very important for the forest community. Right now, the tanoak trees are getting sick and dying from a disease. The disease comes from a mold in the soil that attacks the trees roots. What are your ideas for how to protect the tanoak tree? Tanoak - click to see larger picture
Thimbleberry Thimbleberry grows in sunny spots near the creek. It has sweet berries that are like raspberries. Can you think of animals that might eat thimbleberries? What might happen to these animals if visitors picked the berries? Thimbleberry - click to see larger picture
Western Sword Fern This plant is found all over the redwood forest. The hanging leaves of the fern give places to hide to animals like the Pacific wren and the Sonoma chipmunk. New leaves of the sword fern are eaten by deer. Indians used to use parts of this plant for basketry. Sword Fern - click to see larger picture


Ehrharta grass/Panic Veldt grass This grass is invasive, meaning it does not belong in the forest. Its seeds were stuck to a visitor's shoe and accidentally brought to the redwood forest. Now the grass is spreading all over the forest and not allowing other plants to grow. Animals of the forest will have less habitat if this plant continues to grow here. What would you do to stop the spread of this plant? Ehrharta Grass - click to see larger picture
English Ivy English Ivy is not native to the redwood forest. This means it does not belong. This plant grows over other plants on the ground and grows up the trees. How is the growth of ivy bad for the forest community? English Ivy - click to see larger picture
Forget me Nots The Forget-me-not grows pretty little blue flowers. It grows so thick on the ground that no other plants can grow up. It spreads out and takes the light, water and soil nutrients from other plants. Nothing in the redwood forest eats it. How could this little plant affect the animals of the redwood forest? Forget Me Not - click to see larger picture
French Broom French broom is not part of the redwood forest community. Plants that do not belong in the redwood forest are called invasive. This plant takes over the sunny spots where many plants and animals live. It also grows really tall, which is dangerous to the trees if there is a fire. How is a tall plant more dangerous during a fire? French Broom - click to see larger picture


Crampball mushroom The crampball fungus grows only on dead tanoak trees. It looks like black bumps on the tree trunk and is hard and dry. Crampball mushroom - click to see larger picture
Honey Mushrooms Honey mushrooms grow in large groups. It is one of more than 100 kinds of mushrooms that grow at Muir Woods. This kind of mushroom is food for some forest animals. What makes a good mushroom habitat? Honey Mushrooms - click to see larger picture
Oyster Mushroom This mushroom grows out of dead wood. Several forest animals eat the oyster mushroom, such as chipmunks, squirrels and banana slugs. Why shouldn't people eat mushrooms they find? Oyster Mushroom - click to see larger picture
Scarlet Waxy-cap Mushroom Red mushrooms usually grow all by themselves from the dead leaves of the forest. Can you think of a reason why a mushroom would have a bright red color? Scarlet Waxy Cap - click to see larger picture
Turkey tail mushroom The turkey tail mushroom grows all over the forest. It only grows in dead branches and logs. It looks like the fanned out tail of a turkey. What do mushrooms do in the forest community? Turkey tail mushroom - click to see larger picture


Anna's Hummingbird The Anna's Hummingbird is one of four kinds of hummingbirds at Muir Woods. Hummingbirds drink nectar from bright colored flowers. The sticky monkey flower is one flower that the hummingbird likes to drink. How could hummingbirds drinking from a flower help a plant? Annas Hummingbird - click to see larger picture
Banana Slug The banana slug is a decomposer. It eats dead leaves, some insects, mushrooms and a few live plants. The biggest banana slug grew to be 10 inches long! It lives in redwood forests because it likes shady and wet environments. It does not have many predators. What protections might a slug have to help it survive in the forest environment? Banana Slug - click to see larger picture
Barred Owl The barred owl is not native to the redwood forest. It moved to Muir Woods from another place and is now in competition with other owls for food and hunting territory. Barred owls eat mice, dusky footed woodrats, and crayfish. How does the barred owl affect the owls that were already living in the forest? Hear the call of the Barred Owl. Barred Owl - click to see larger picture
Black-tailed Deer The deer is the biggest mammal to live at Muir Woods. During the day the deer eats many different kinds of plants and keeps certain plants from growing out of control. Animals that eat only plants, like the deer, are called herbivores. Can you think of an animal that hunts deer for food? What might happen to the forest if there were no predators to hunt the deer? Black-tailed Deer - click to see larger picture
Coho Salmon When a salmon turns three years old, it swims from the ocean back to the place it was born. It fights against the creek current to get there. Once it arrives the salmon digs a nest, called a redd, and lays eggs. Other spawning salmon fertilize the eggs. After the fish have spawned they die and become food for other animals and plants. Most salmon do not ever make it back to their birthplace to spawn. What reasons can you think of for this? Salmon Smolt - click to see larger picture
Convergent ladybugs The convergent ladybug spends most of its life in a hibernation state, called estivation. Thousands of ladybugs cluster together to keep warm and keep predators away with their smell and color. Ladybugs gather on logs, trees and bushes for protection. What protections does the ladybug have by doing this? Ladybugs - click to see larger picture
Crayfish Crayfish are crustaceans that live in freshwater creeks. They are invasive in the redwood forest community, which means they do not belong. They eat live plants, dead animals, and eggs of fish and frogs. How do the crayfish threaten the salmons' future? How might they be stopped? Crayfish - click to see larger picture
Dusky-footed woodrat The Dusky-footed woodrat is nocturnal - it comes out at night. What adaptations does this animal have to help it survive in the forest? What animals might hunt for a Dusky-footed woodrat? Dusky Footed Woodrat - click to see larger picture
Grey Fox The grey fox is an omnivore at the top of the food chain. It hunts other small animals once the sun has gone down. It also eats plants and berries. It can use its hooked claws to climb trees and search for food in the tree tops. What might happen to this animal if some of its favorite foods disappeared? Grey Fox - click to see larger picture
Grey Squirrel Grey squirrels are often seen in the redwood forest during the daytime searching for food. Squirrels eat plants, nuts and seeds, fruits and fungi. They also store food to eat later. One important source of food is acorn. If there were no more acorns how do you think squirrels would be affected? How would the rest of the forest community be affected? Grey Squirrel - click to see larger picture
Hairy Woodpecker Hairy woodpeckers make their home in the redwood forest and live there year round.
They spend much of the day pecking into the bark of dead bay trees in search of insects.
How might removing some of the dead trees in the forest affect this bird?
Hairy Woodpecker - click to see larger picture
Harvestman spider The harvestman is an arachnid, meaning it has eight legs. It is different from other spiders because it cannot make a web and does not have venom to stun its prey. It lives in the dark holes created by the roots of the redwoods. To protect itself it makes a stinky odor that keeps enemies away. Harvestman Spider - click to see larger picture
Millipede The millipede is a decomposer and eats decaying plants. It lives in the leafy soil and lays its eggs there. Millipedes defend themselves by rolling up into a tight curl. Its body's armor creates a strong shell. Millipede - click to see larger picture
Northern-Spotted Owl This owl is native to MuirWoods, which means it belongs to the redwood forest community. It is a nocturnal hunter and is at the top of the food chain. It is a carnivore - it eats wood rats, squirrels, other small mammals and sometimes snakes or insects. This owl is an endangered species. What ideas do you have for how to protect this animal from extinction? Spotted Owl - click to see larger picture
Pacific wren The Pacific wren is a golf-ball sized bird. It spends most of the day hopping around the skirts of the sword ferns. It hunts for small insects in the duff layer of the forest floor. The Pacific wren sings a loud and long song. Why do you think birds sing? Pacific wren - click to see larger picture
Pileated woodpecker This is the largest woodpecker in the United States. It makes its home in the redwood forest and eats insects that live inside of dead trees. It uses its specialized beak to bore into wood. What other reasons might a woodpecker bore into wood? Pileated Woodpecker - click to see larger picture
Redwood Snail The Redwood Snail is often found crawling around the redwood forest with its home on its back. These land mollusks constantly secrete slime to help them move around the forest. They need plenty of water and cool moist weather or they could dry up and die. Redwood Snail - click to see larger picture
River Otter The river otter makes its home in the branches and logs in the creek. It hunts for fish, crayfish and frogs at night usually. The otters left Muir Woods for a long time, but now they have returned. Why might the otters have left? What might have led to them returning? Do you think they would leave again? Otter - click to see larger picture
Salamander The pacific giant salamander lives in moist places. The shade and water of the redwood forest makes a good home for salamanders. This salamander can grow to be as long as a ruler you use to measure. When scared, the salamander makes a sound like a barking dog. It eats banana slugs, wood mice and small insects. What would happen to the salamander if its habitat was no longer moist? Salamander - click to see larger picture
Salmon smolt After a salmon egg hatches the young fish, called alevin, lives under rocks. Once it can hunt for its own food it comes out and is called a smolt. They live in the freshwater creek for one year. At the end of the year they will go out to live in the ocean. Only the strongest fish will go to sea. What do you think happens to the other young fish? Smolt - click to see larger picture
Small Insects Small insects bore holes into dead wood and logs. They are eaten by woodpeckers, pacific wrens, Harvestman spiders, and more Small insect holes - click to see larger picture
Snowy Egret The egret is a white bird that lives near wet places. They do not live in the redwood forest, but sometimes visit to find food. The egret hunts salmon smolts, crayfish, and small insects in the creek. What is the egret here hunting for? Egret - click to see larger picture
Sonoma Chipmunk The Sonoma chipmunk eats seeds, nuts, berries and other plants. Animals that do not eat other animals are called herbivores. The chipmunks scurry around the forest in search of food during the day. Can you think of an animal from the forest that might depend on the chipmunks as a food source? Chipmunk - click to see larger picture
Steelhead trout The steelhead trout is related to the salmon. It lives for one year in freshwater and grows up in the ocean. It also returns to freshwater to spawn. The steelhead trout does not die after spawning - it goes back to sea. This animal is threatened with extinction. What animals of the redwood forest might depend on these fish? What happens if the salmon go extinct? Steelhead Trout - click to see larger picture
Steller's Jay Steller's Jays are the blue birds seen near the forest's sunny edge. The bird eats insects, seeds and nuts, but often scavenges for human food. How might human food affect the health of Steller's Jays? What could you do to help protect them? Stellar's Jay - click to see larger picture
Wood mice Small rodents are common in the redwood forest. They are nocturnal and will eat a variety of plants, seeds and nuts. What adaptations do rodents have to help them survive? Why does it need these? Wood Mouse - click to see larger picture