Field trip to China Camp, Mt. Tam, Muir Woods
In the blazing heat on September 24, 2019, the Environmental Forum of Marin’s (EFM) Masterclass 46 explored plant communities and Marin baylands. Our first stop was China Camp State Park and a hike over Turtleback Hill. Environmental Forum’s Nona Dennis and Kathy Cuneo were our guides for this first leg. Nona described herself as having the “wide lens” perspective and Kathy as the “zoom” lens. Nona provided a historical perspective of the area and Kathy took us deep into natural processes and plants.
China Camp State Park
Purple needlegrass (Nassella pulchra), california’s state grass
We climbed Turtleback Hill and stopped at one of the many panoramic views overlooking the Marin baylands. Baylands are the land between the highest and lowest reach of the tide. Nona showed us a historic map from the 1850’s of the San Francisco Bay which extended much farther than it does today. She described the land of that time: 22 million acres of the central valley and the coastal bluffs were prairie grasslands covered in wildflowers such as poppies, brodiaea, and lilies and perennial bunch grasses including the dominant Purple Needlegrass. The roots of these native grasses are alive underground year-round. In early spring, stems emerge and the grasses flower from April to June.
Purple Needlegrass (Nassella pulchra) was designated as the California State grass in 2004.
When longhorn cattle ranching came to Marin County in the 1700’s, its practices replaced the native perennial grasses with non-native annual grasses. The intent of cattle ranching at that time was to produce hides and tallow rather than meat. Cattle relentlessly grazed the shoots of the bunch grasses. Eventually the grasses were exhausted by the quickened production cycle and died out. Ranchers built dykes and raised rye and oats on the wetlands. The wild oats established quickly and overtook the native perennials. The annual grasses started their growing cycle earlier than the perennial bunch grasses which starved the bunch grasses of sunlight.
The mighty oak
We turned our attention from the flat marshlands to the rolling oak hills. Kathy, aided by detailed charts, gave a captivating description of the photosynthesis and respiration processes using oak trees as an example. The oaks take sunlight through their leaves and make sugar. They convert carbon dioxide (CO2) into carbohydrate (sugar). Inside the oak leaf, the chloroplasts move up and down in response to light and heat producing oxygen. The oxygen diffuses out and the CO2 diffuses in. The tree takes in nitrates to form amino acids which form a protein chain. This chemical reaction uses glucose (sugar). Over millions of years, plant carbons were fossilized in the earth to create today’s fossil fuels such as coal, peat, oil.
Oaks are a keystone species meaning they give more than they take. Oak landscapes support a rich ecosystem of birds, insects, lizards and more.
One species that relies on oaks is Acorn Woodpeckers, which live in groups and rely on their young to gather acorns to feed the group. They place the acorns in granaries to dry. Granaries typically contain from 1,000 to 50,000 acorns (wow!) each fitted into a drilled hole in a dead branch. The woodpeckers transfer the acorns to smaller holes as the acorns dry. Each scrub jay and squirrel caches about 2,000-5,000 acorns in the ground and retrieves about 30-50% of them to eat. This leaves many acorns to germinate into oak sprouts. Read more about acorn woodpeckers in Bay Nature.
For thousands of years, the Coast Miwok relied on acorns as a staple food and they tended the oaks to ensure a plentiful harvest. Learn more about the Coast Miwok and their sustainable land management practices in these books:
Chief Marin by Betty Goerke, a biography of Marin County's namesake, a Coast Miwok Indian who resisted Spanish settlement of the county.
Tending the Wild by Kat Anderson, Native American Knowledge and the Management of California's Natural Resources
China Camp Marsh plants
We walked back down to the marsh to take a closer look at the plants living there and to learn about biomass productivity. China Camp is a well-studied marsh and the data collected over the decades is used as a baseline to compare with other marshes.
The marsh is dominated by perennial Pickleweed or Pacific Glasswort (Salicornia pacifica) and Saltmarsh Cord Grass (Sporobolus alterniflorus). We examined salt crystals on the stems of Cord Grass and Salt Grass (Distichlis spicate). These salt marsh plants must use energy to secrete the salt that builds up in their bodies. The Cord Grass is hollow so it can trap air to breathe when its roots are underwater. Tall Gumplant (Grindelia stricta) and tiny Marsh Jaumea (Jaumea carnosa) add bright patches of yellow to the landscape. The Cord Grass is beaten down during winter storms and its particles join other dissolved plants to create a “sea soup” that along with minerals eventually sinks to the bottom of the bay. These plant particles get eaten by mussels, clams and shrimp.
Biomass
When you measure the biomass (plant material) of different plant communities, the salt marsh comes up short compared to the large Redwoods forests. However, looking at the amount of biomass that is produced in a year (“productivity"), the salt marsh is king.
Biomass for plant communities (kilograms per square meter)
3200 Redwood forest
500 bishop pine forest
5 chaparral
3 coastal scrub
2 salt marsh
Biomass net annual productivity (Measures the weight of plants including new growth and newly wilted, dried and weighed.)
2000 salt marsh (attributed to one very productive salt marsh in the North!)
1200 bishop pine
900 salt marsh (average in Bay Area)
More than 60 species of waterfowl and shorebirds migrate through the highly-productive China Camp marsh every year.
Mt. Tamalpais
Terri Thomas, EFM’s Director of Ecology, guided us through the chaparral terrain along the Panoramic Trail on Mt. Tam. Manzanita is dominant in this landscape and we learned about botanist Alice Eastwood’s interest in Mt. Tam and in this rugged chaparral plant. She came to San Francisco in 1892 to be head of botany at the California Academy of Sciences. Eastwood identified and named five different species of manzanita on Mt. Tamalpais. Her beloved chaparral plant specimens were among the 1497 rare specimens she saved from burning in the disastrous 1906 fire, following the earthquake, that destroyed the original California Academy of Sciences on Market Street in San Francisco.
Alice Eastwood (1859-1953) Botantist extraordinaire
The chaparral plants such as manzanita battle with the Douglas Fir forest for dominance on Mt. Tam. When fire burns the land, the chaparral grows back faster than the forest. In times without fire, the forest overtakes the chaparral.
Before we left Mt. Tam, Kathy Cuneo pointed out a fun observation to share with small children. The Douglas Fir cone is a hiding place for many tiny mice. Not really, but the shaggy extensions of the cone look like two legs with a tiny tail between the legs.
Muir Woods
We moved from the heat of Mt. Tamalpais to the cool ancient Redwood groves of Muir Woods National Monument. Muir Woods is located between the slopes of Mt. Tamalpais and Muir Beach on the coast.
Mia Monroe, who is Site Supervisor of Muir Woods led our tour and described how Muir Woods was established as a national monument. Local residents Elizabeth and William Kent took the advice of their friend John Muir and bought this land in 1905 and donated it to the federal government as public land. The Kent’s were interested in this particular forest for a number of reasons: it was primeval forest that had never been logged, it was near urban areas for easy public access, and it was close to research institutions such as UC Berkeley and Stanford. The mission of Muir Woods is to preserve and protect the forest. The park stewards go to great lengths to preserve its pristine natural state which is not easy with a million visitors a year. The park prohibits food in the forest and doesn’t have trash dumpsters which are noisy to empty and attract pests. They even use quiet cash registers in the gift store.
Understanding that the land and its communities are connected, Muir Woods is using the One Tam landscape-scale stewardship model to partner with many other agencies in the area including the Marin Water District to manage the Redwood Creek watershed that is at the heart of the land. According to One Tam, “Landscape-scale stewardship is how we work together across boundaries to care for the places we love, enjoy, and depend upon, and how we continue to renew and sustain these places for current and future generations.” See the Redwood Creek Watershed Vision 2003-2015. Redwood Creek Watershed did an assessment of the watershed in 2011 and identified many concerns including lack of fire, invasive species, water storage and creek erosion and sediment which were a serious threat to the native salmon.
Redwood Renewal projects
Redwood Renewal aims to be transformative on a landscape level. The park took a hard look at their own processes and infrastructures. In looking inward, the park discovered to their dismay that the fabricated concrete boulder riprap walls, built by the California Conservation Corps, and the way they had channelized the creek had destroyed habitat for the federally endangered Coho salmon.
The park is working on a new water line and upgraded systems. They are removing the riprap walls and returning native vegetation to the creek banks. The aim is to create a more absorbent sponge-like capacity to hold water and let is seep out slowly rather than water rushing through the riprapped channels and washing away all the gravel. Now, when a tree falls in the creek, the park leaves it in place to decompose and serve its natural purpose of breaking the flow of water and providing nutrients and hiding places for fish. Before, the park “groomed” the landscape to make it more attractive by removing fallen trees. Removing the riprap is just one of the many projects slated for 2018-2023.
Salmon Habitat
We met Carolyn Shoulders, a Natural Resources Specialist with the Golden Gate National Parks Conservancy. She is managing the creek restoration project that is removing the riprap walls and restoring the creek to its natural processes which will benefit salmon. I also spoke with Carl, a recent UC Davis graduate who is biology manager for the project. He measures the turbulence of the water and rescues critters that are affected by the construction work.
The restoration work includes stabilizing the creek banks by planting native riparian plants such as Giant Chain Fern (Woodwardia fimbriate), Western Maidenhair Fern or Five Finger Fern (Adiantum aleuticum), California Spikenard or Elk Clover (Aralia californica).
Call of the wild
When fresh water from winter storms finally grows to enough volume to break free from the banks/dunes and reach the ocean it sends a signal to salmon to come home to spawn. Salmon need gravel to lay their eggs in, and “nursery” habitat for babies to shelter and grow. That’s what they’ll find when they return to the restored Redwood Creek!
Redwood trees
Redwood trees continue to grow skyward their whole life to heights of 300 feet. Their red color comes from tannins in their bark which act as a defense against insects. Unlike people, redwoods love fire and floods. These events provide food and water and clear out diseases. Redwoods can reproduce both sexually and asexually. In the former, the male pollen at the top of tree drifts down to the tiny female cones on the lower branches. Redwoods are the largest trees yet have the smallest cones. In asexual reproduction, the tree creates clones. When a tree falls, it opens an area of sunlight in the forest giving smaller trees and plants a chance to grow. The fallen Redwood produces a burl that sprouts genetic clone trees who use the nutrients from the parent tree and the sunlight above to grow. A burl is a knobby growth full of unsprouted bud tissue. It is a storage compartment for the genetic code of the parent tree.
More interesting facts about Redwoods (source: sempervirons.org)
1. TALLEST TREE ON EARTH
Your local coast redwood tree can grow to 300 feet or more, compared to the tallest pine tree at 268 feet or the tallest tanoak at 162 feet — yet its root system is only 6 to 12 feet deep. Redwoods create the strength to withstand powerful winds and floods by extending their roots more than 50 feet from the trunk and living in groves where their roots can intertwine.
2. AS OLD AS THE DINOSAURS — ALMOST
The earliest redwoods showed up on Earth shortly after the dinosaurs – and before flowers, birds, spiders… and, of course, humans. Redwoods have been around for about 240 million years and in California for at least 20 million years, compared to about 200,000 years for “modern” humans.
The rise of environmental law
Our last lesson of the day involved The Walt Disney Company and a glacial valley in the southern Sierra called Mineral King. In the 1960’s Walt Disney was successful in responding to a bid from the Forest Service to develop Mineral King as a ski resort. Preservationists, led by the Sierra Club fought Disney in court and eventually won a landmark ruling in 1971 establishing that ecosystems of national importance have a standing in court. The Sierra Club Legal Defense Fund, founded in 1971 to fight the Mineral King resort in court, lives on today as Earthjustice.
Read more about this landmark environmental battle.
Earthjustice
Years of political maneuverings had failed to halt the resort, so a group of visionary lawyers took a risk that changed environmental protection forever — they filed a lawsuit to protect Mineral King from development.
The case climbed all the way to the U.S. Supreme Court, which in 1972 ruled in favor of Walt Disney. But this apparent defeat was actually a thrilling victory: a footnote in the majority opinion indicated that Mineral King’s lawyers could have demonstrated that private citizens who use the valley would have been irreparably harmed by the development.
And that’s exactly what we did. Earthjustice — known then as the Sierra Club Legal Defense Fund — filed suit again, in partnership with nine plaintiffs who visited Mineral King often and would be harmed by Disney’s development. This precedent-setting action secured standing to sue for private citizens, confirming the public’s right to fight for the environment in court. – Earth Justice “About our History”