Ring Mountain Preserve

A mountain like nowhere else in the world


The rolling grasslands of Ring Mountain, and the broader region, are the ancestral home of the Coast Miwok, who are indelibly connected to this place both past and present. Since 1981, Ring Mountain has been protected as a public open space with one of the most sensitive ecological and culturally significant landscapes in Marin, and it is a place that has witnessed many changes.


The colonization of present-day California by the Spanish in the 1700s set off a cascade of impacts. These impacts were felt by all who lived there, but also on the land itself. What would become Ring Mountain was cultivated in a European style that introduced cattle and horse grazing, along with many weedy non-native plants, into its pristine grassland. Landownership shifted to the Reed family in 1834, but the hilltop became associated with George E. Ring. Ring owned nearby land and was a County supervisor at the turn of the 19th century when this collection of rocky hills started to be called "Ring Mountain".


Ring Mountain was spared from development, except for a cold-war military installation in the 1950s. The eastern peak was to make way for anti-aircraft guns and buildings. One little-known clue to this history is the presence of radiolarian chert, a type of red rock imported in a gravel form from the Marin Headlands for this installation. Like stumps of old fences, the military left these out-of-place rocks behind when they decommissioned this installation in the 1960s.


Early on, Ring Mountain was recognized for its unique geology. In 1890, a new mineral, named lawsonite, was identified here. Prominent geologist Salem Rice later wrote, "Most of the rare and unusual rock types at Ring Mountain have been found… at other localities. However, it appears that the diverse assortment of such rocks at Ring Mountain is unique and not known to occur elsewhere." Ring Mountain is dotted with boulders of blueschist and a variety of metamorphic rocks (including serpentinite). Turtle rock is an example of one of these boulders, which has inclusions of other rocks and minerals, like mica, that can make the surface of the rock sparkle on a sunny day.


During the mid-1960s, Reed family descendants moved cattle and horses off Ring Mountain, and sold over 400 acres to a developer. The prospect of development triggered a lengthy, multi-year effort to rally support for preserving Ring Mountain.


In 1972, Dr. Robert West found an unusual flower high on Ring Mountain that had previously escaped botanists’ detection. This plant was the Tiburon mariposa lily, a rare plant that grows nowhere else and became a symbol of Ring Mountain and its biodiversity. In addition to the Tiburon mariposa lily and six other rare plants, there are at least an additional 337 plant species, 45 bird species, 50 lichen species, and hundreds of insect species that call Ring Mountain home. This high diversity is due to the preserve’s serpentine soils and grassland ecosystems.


Before moving to Tiburon with her husband George in 1958, Phyllis Ellman served in the U.S. Army, achieved an advanced degree in chemistry, and worked as a biochemist. As a member of the Marin chapter of the Native Plant Society, she became known as "Mother Botany" for her extensive knowledge of Marin wildflowers. Ellman led the campaign to save Ring Mountain place from development. Today's most popular trail at Ring Mountain bears her name in recognition of her contribution to the preserve.


The Nature Conservancy purchased Ring Mountain in three separate transactions – 1981, 75 acres; 1982, 40 acres; 1984, 270 acres – and managed the property as a nature preserve. In 1995, The Nature Conservancy conveyed the title of Ring Mountain to Marin County, while continuing to hold a conservation easement over the property. The conservation easement requires that the Preserve be used for scientific and educational purposes and be managed as a natural area.


Over the years, The Nature Conservancy has continued to support Ring Mountain in many ways. Since 2011, The Nature Conservancy has made funds from a bequest by Mr. J. Lowell Groves available for Ring Mountain conservation, via an ongoing grant. This currently funds the Ring Mountain Stewardship and Habitat Restoration Program. The program is designed to be efficient, and outcome-oriented, to serve as a flagship conservation site and management template for Marin County, and maintain long-term continuity in the efforts to preserve Ring Mountain.