Next volunteer workday

June 21

9:00-11:00 am. Meet at the Cortereal Ave. entrance to the trail. If interested in participating, and would like us to send you details when available, please click here

Alerts

Poison oak and toxic mushrooms

Best to entirely avoid these hazards by staying on the paved parts of the trail, and by keeping children close and dogs on leash.

more info

Reminder

To keep your pets safe from seasonal hazards please keep dogs on the path and on leash. Thank you.

Sightings

Much to Discover

The trail is teeming with life from deep underground to high above the canopy. Most is unseen or barely noticed.

Yet here, natural systems are humming 24/7, providing the air we breathe, recycling decaying matter, storing carbon and revitalizing new growth. Simple acts like keeping dogs on leash, carrying out trash, and minimizing noise levels are vital to keeping trail wildlife healthy into the future. Learn more about the local ecology here.

Seasonal Highlights

winter

Coast Redwood

The coast redwood is the tallest tree on Earth, the fastest-growing conifer and can live more than 2,000 years. A stand of redwoods, like the one at the La Salle entrance, can create its own rain by collecting fog. The redwood ecosystem supports a unique mix of mammals, birds, and plants including salamanders, owls and ferns.

Great Horned Owl

One of the largest owls, these birds are so well camouflaged that they’re rarely seen, but their “hoot” calls can often be heard echoing up and down the trail after dark. Generally nocturnal, their large yellow eyes can pinpoint prey in extremely low light. They can also hear sounds as far away as 10 miles.

Ladybugs

Attracted by the pheromones plants exude when under attack, these beetles can eat up to 5,000 aphids over their one-year lifespan. During the fall, ladybugs fly eastward with the prevailing winds, often landing on the trail and other East Bay hill locations where they huddle on leaves and branches — often in vast clusters — to stay warm through the winter.

spring

Lesser Goldfinch

“Lesser” refers to its size — not its value or importance — and this species is the smallest of the American goldfinches. Breeding males carry flashy yellow plumage and sing a medley of trills, wheezes and stutters to attract mates. Finches are among the dozens of native and migrating bird species to see and hear on the trail.

Hare’s Foot Inkcap

As they pop up out of the soil and leaf litter during the rainy season, these mushrooms resemble rabbit’s paws. Once it unfurls, the fungus is delicate and short-lived, lasting only a few hours before dissolving into a black inky liquid — a process called deliquescence.

Trillium

Though increasingly rare in the Bay Area, trillium were recently discovered on the trail. Beautiful and distinctive, trillium (true to their name) are a study in threes. Their three-petaled flowers appear in many shades from white to blood red. Like poinsettias, trillium have bracts, which are not true leaves but are structures associated with their flowers. Ants and yellow jackets are the primary agents that spread trillium seeds.

summer

Cow Parsnip

Often toxic to us (best to not touch it), the cow parsnip is an important food source for deer, birds and small mammals and a habitat for larval butterflies and bees. Though a member of the carrot family, cow parsnips like those along the trail can produce 16” leaves and grow to a height of 10 feet.

Western Monarch Butterfly Caterpillar

Luckily we have native milkweed plants growing along the trail, which are key to the butterfly’s survival. Milkweed is poisonous to almost every animal. But monarchs have evolved an ability to tolerate the poison. The caterpillars munching on the leaves actually store it in their bodies so that, even through metamorphosis, adult butterflies keep their toxicity to predators. The areas around milkweed plants need protection as a caterpillar can venture up to 30 feet away to form its chrysalis.

Western Fence Lizard

Also known as blue-bellies, the adult males have brighter blue belly scales that attract females. Basking in the sun or scurrying about the trail, please honor their push-up displays as they may feel threatened. Deer tick nymphs feed on the lizards, but their blood has a protein that kills Lyme disease bacterium. This could be why Lyme disease rates in California are lower than in other parts of the country.

autumn

Red Shouldered Hawk

The distinctive markings of an adult red shouldered hawk include a banded rufous chest, a reddish shoulder and neck area and a pronounced checkerboard/barred pattern on the wings and tail. A juvenile looks very different. The chest area is mostly white with a banding pattern that runs in the opposite direction from an adult’s. Like most raptors, females are larger than the males. Frequently seen along the trail, and high above it, is a red shoulder hawk that nests here year after year.

Coast Live Oak

Native to this area and found throughout the trail, these oaks support biodiversity by providing shelter, nesting opportunities and food. Dozens of mammal and bird species rely on their fat- and protein-rich acorns. The shape of their leaves capture dew and mist, helping the trees survive through droughts. Though the coast live oak always maintains some leaves, those it sheds create habitats for insects, amphibians and soil microorganisms. One species of moth would vanish entirely without the oak’s leaves.

Coyote

Vital to maintaining a balanced ecosystem here, it’s likely you won’t see coyotes on the trail, but their yips and howls are often heard. In winter they mate and in spring rear their pups. Coyotes may be more active at those times. Though they rarely approach humans, be alert and keep children close and dogs on leash (see Bay Area Coyote)