Natural History

Huckleberries dominate the redwood understory; their thick, bushy branches provide shelter and nesting habitat for forest birds, which eat the berries and spread the seeds throughout the forest. Ferns, elk clover, and horsetail plants grow along the creek. Portola Redwoods State Park is also one of the last remaining homes of Dudley’s lousewort, a plant dispersed by ants and banana slugs that thrives among old-growth trees.

The dominant tree in Portola is the redwood, but tan oak, madrone, California bay, bigleaf maple, and Douglas-fir also thrive. On dry, south-facing hillsides and high ridges, redwoods give way to live oak, manzanita and chamise.

Coho salmon and steelhead trout spawn in Pescadero Creek. Old-growth trees provide important habitat for the marbled murrelet, an endangered seabird that nests high in the redwoods. The park’s mammals include gray foxes, black-tailed deer, raccoons, gray squirrels, coyotes, bobcats and mountain lions.
   
LEOPARD LILIES
From May to July, look for bright orange leopard lily blossoms. With leopard-like spots on their petals, these showy flowers grow on stout stems 3 to 6 feet high. Their leaves are narrow and pale- to deep-green, in whorls. Hungry hummingbirds and butterflies pollinate the lilies as they sip the nourishing nectar. Their seed pods, held upright like a salt shaker, contain hundreds of seeds. But very few ever make it to the ground before the flowers are eaten by deer. During winter rains, dormant lily bulbs wash downstream, where they start new colonies. 
Enjoy—but please don't pick.


   
BE AWARE
Ticks are common in this area; some may be infected with Lyme disease. Tuck in cuffs while hiking, and check for bites. 

Attracted to meat and sugar, wasps called yellowjackets live in cavities or underground. They can deliver repeated, painful stings. 

With leaves in groups of three, poison oak may be green, red, shiny, dull, or even completely absent in winter. Even leafless stems can cause a serious reaction. Stay on trails to avoid contact with this plant.

Growing in damp areas such as stream banks, stinging nettles have large, spear-shaped leaves with stems up to 6 feet tall. This plant is covered with tiny, stinging hairs that can inflict a painful reaction if even lightly touched. 
   
Climate Change
In a time of climate change, redwoods are an asset. Their size and longevity help them store more climate-altering carbon dioxide than other plants. Even old redwoods continue to grow, each year adding more carbon-filled wood than smaller, younger trees. After redwoods die, their rot-resistant wood keeps that carbon out of the atmosphere for a long time. Could redwoods be harmed by climate change? Well, they don’t seem to be suffering so far. But scientists say that increasing temperatures, along with decreasing summer fog, could pose a threat in the decades to come. To find out more about the effects of climate change in California’s redwood parks, go to this Save the Redwoods League web page.