What do thousands of blooming Contra Costa goldfields and a wedge of blue cheese have in common? Both can be linked to a conservation easement, a tool used by nonprofit land trusts and public agencies to conserve land, support agriculture, and protect natural resources.

A conservation easement is a legal agreement that a land trust or public agency can make with a landowner. Under these agreements, an owner willingly relinquishes the right to develop their land and agrees to use the land in ways that align with specific conservation goals. In exchange, the owner usually receives tax benefits, and in some instances, gets paid for forfeiting their development rights in perpetuity. The land trust or public agency assumes responsibility for monitoring the land and enforcing the terms of the conservation easement. Of the nearly 1.2 million acres of permanently protected land in the San Francisco Bay Area, 20 percent is privately owned and protected by voluntary conservation agreements, according to the Bay Area Protected Areas Database compiled by the Bay Area Open Space Council and the GreenInfo Network.

There are different kinds of conservation easements, from those that protect working agricultural and forest landscapes, to others that provide added protection to land owned by a public agency, or still others that allow for public trail access on the edge of a coastal farm. Every conservation easement is unique, which makes them a handy, and often complex, tool. “We don’t put a conservation easement on a piece of property just to extinguish development,” said Linus Eukel, executive director of the John Muir Land Trust. “We protect land for affirmative reasons, such as having high-value habitat, or the potential for public trails or recreation.”

The protection of a stand of Contra Costa goldfields in its namesake county took seed when the California Department of Transportation set out to widen a bursting commuter corridor on State Route 4. Their work encroached upon habitat for the federally-endangered goldfields, a species of wildflower which has almost completely disappeared due to development and non-native grasses. As mitigation, Caltrans granted John Muir Land Trust a conservation easement in 2002 on a 30-acre preserve near Hercules where about 20 of the diminutive goldfields still bloomed. After years of well-managed grazing practices, the annual blooms number around 50,000.

The cheese in West Marin has a different story — and a different land trust. Formed in 1980, the Marin Agricultural Land Trust (MALT) is the first purely agricultural land trust in America. Since 2001, MALT has required “mandatory agricultural use” for every new conservation easement. The organization also encourages landowners with older easements to update those agreements to affirmative easements with mandatory agricultural use. The origin story for the cheese began in 2005, when MALT purchased a 714-acre conservation easement from the Giacomini Ranch, a traditional dairy farm in Point Reyes Station since 1959. The Giacominis used the cash inflow from the sale of the easement — coupled with innovative ideas from the family’s next generation — to evolve from a traditional dairy farm to an award-winning cheese purveyor.

MALT has protected nearly 50,000 acres of land in partnership with 81 families. The organization’s aim is to protect 100,000 acres by 2040, a $250-300 million goal. “It’s ambitious, but we think it can be done,” said Jeff Stamp, MALT’s director of conservation.

There are 1,363 land trusts in the United States and over 20 in the Bay Area; each one utilizes conservation easements in ways that make sense for them. “An easement is an important tool in the conservation toolkit,” said Noelle Thurlow, director of land programs and transactions for the Peninsula Open Space Trust (POST). In the last 40 years, POST has protected 75,000 acres of open space, farms, and parkland. The organization primarily acquires private land and turns it over to a public agency such as the county or the Midpeninsula Regional Open Space District.

Sometimes a conservation easement can be used creatively. For example, a few years ago POST purchased the 353-acre Alpine Ranch in La Honda adjacent to Sam McDonald County Park. To add a layer of protection to the property’s natural resources that includes an abundance of redwood trees, the Midpeninsula Regional Open Space District bought a conservation easement from POST. POST will use the funds to protect more redwoods on another property, and eventually donate the land to the county, which will add it to the park. The District will retain the conservation easement and enforce its terms.

POST also holds conservation easements, which range in size from a few acres to 2,000 acres. “The commitment that land trusts make to a conservation easement is significant,” said Thurlow. A conservation easement is detailed in a legal document that is attached to the deed of the land. The language is different in each case because every property is different, but all easements protect land in perpetuity, even if the land changes hands. That’s why land trusts have some version of “forever” in their mission statements.

“Perpetuity is a long time, and it’s a challenge to find the right balance between protection and flexibility,” said Thurlow, who explained that each document needs to provide flexibility for the landowner, while ensuring that the restrictions are strong enough for protection and conservation of the land and its resources.

A conservation easement can be a highly collaborative partnership, and most land trusts invest in the land to help the owner stay in compliance. For example, a land trust might work with a landowner to improve water distribution on the property, or assist them in securing a grant or partnering with a local resource conservation district. A land trust can help address resource concerns by incentivizing a landowner to improve operations. For example, MALT is part of a larger community effort to enhance carbon farming and study its potential as a solution to climate change.

The Conservation Lands Network, a regional association of funders, planners, and conservation organizations, has set a year 2025 goal to protect 20 million acres of land vital to the biodiversity of the Bay Area through a variety of methods including conservation easements. We’re a little over halfway there, but pressure is mounting. The land is expected to provide a kaleidoscope of uses, such as housing, resiliency to climate change, clean air and water, and outdoor recreation for health and well-being. “If we want to protect the heritage and resources of the Bay Area, this is one of the tools we need to be successful,” said Thurlow.

Aleta George covers open space for the Monitor.