One way Sonoma Ecology Center has become a leader in climate action is through a carbon-negative opportunity called biochar—a specialized form of charcoal that can be used as a soil amendment in commercial agriculture or one’s own garden, as a water filtration medium, or even as a sustainable replacement for many industrial fossil inputs.

Biochar is produced by heating woody wastes from forest thinning or agriculture in a low-oxygen environment. There are many different ways of making biochar create different characteristics suitable for different end uses. 

Biochar can be made from many different types of “waste” biomass. We strongly believe that biochar should be made ONLY from sustainably managed sources, which is critical

from both an environmental and business perspective, and that when sourcing biomass from forest environments great care must be taken to preserve and minimize damage to forest ecosystems. Most of the biochar made in California today is produced from unmerchantable materials created during fuels reduction work for fire safety, or from drought and beetle-damaged trees that are dying in record numbers from climate change.

Biochar has a unique physical structure, with thousands of tiny pores that hold the nutrients and water for the plants’ roots to access and enjoy. In many ways it’s akin to a coral reef in the ocean, acting as a natural attractant, sanctuary, and incubator for microbial life and fungi by creating infrastructure for billions of organisms to thrive.

Bags of biochar are available at our Saturday morning Harvest Markets at Sonoma Garden Park

Benefits of biochar produced for use in soil include: 

  • Every pound of biochar placed in the ground balances out some of our continuing emissions of carbon from cars or power plants or homes. The underground biochar helps prevent greenhouse gases such as methane and C02, produced from decaying plant matter, from entering the atmosphere—about 2.5 pounds of C02e for every pound added to the soil.
  • Biochar holds water, helping combat drought—plants have more water available to them for a longer period of time.
  • Biochar increases food security by enhancing soil fertility and conservation of nutrients.
  • Research done by Sonoma Ecology Center and other experts shows that biochar in the soil can have distinct positive effects on plant health and fruit and vegetable production.

EnviroLeaders assisting our Restoration staff with pot trials at the Sonoma Garden Park nursery with native trees using a biochar/compost blend compared to a control blend using compost and soil only.

For these reasons, Sonoma Ecology Center co-founded The Sonoma Biochar Initiative (SBI), a project dedicated to promoting biochar education and its sustainable production and use throughout California. We collaborate with our strategic partners (such as the Redwood Forest Foundation, Goldridge, Napa, and Mendocino RCD’s, and Sonoma Water) to educate local farmers, foresters, vineyard managers, government officials, businesses, and other stakeholders on the advantages of producing biochar to better utilize surplus materials coming out of our forests to reduce fire hazards and improve community resiliency, and then using the biochar to enhance agricultural productivity while reducing GHG emissions.

We recently received a Cal Fire Urban Forestry grant to purchase a biochar production system. In partnership with a Bay Area tree service (A Plus Tree Company) which will operate our machine, we will start producing our own high-quality biochar later this year from wood chips that, up to now, have been sent to landfills where they degrade over time into greenhouse gases like methane. Much of the biochar made in our machine will be distributed to community gardens in disadvantaged areas of the East Bay and North Bay areas to help build food security and reduce water use.

We invite you to learn more about this program’s recent activities.