Prescribed Burns at Van Hoosear Wildflower Preserve

Unplanned wildfires can be devastating, but planned burns can effectively remove excess flammable vegetation, manage invasive plants, and revitalize native plant communities such as the Preserve’s wildflower meadows. 

Since 2004, we have worked with the owners of the Van Hoosear Wildflower Preserve to co-manage the wildflower meadows and grasslands, oak woodlands, and riparian habitats of the Preserve. This 162-acre property is protected forever against future development, to preserve its beauty and its rich and rare mix of native plants and animals. 

Several non-native, invasive plant species grow in the Preserve. Some of them are not edible by cattle, so despite careful summer grazing, their populations continue to expand. Part of our stewardship includes prescribed burns. These are controlled fires, planned and monitored closely, that clear away built-up flammable vegetation and reduce invasive plants like Medusahead, an invasive grass that creates a thick layer of persistent, flammable thatch that smothers native grasses and wildflowers and creates a thick layer of dry thatch.

Burns are timed for cool, calm conditions and led by an experienced burn boss. After a burn, the land recovers quickly. The following spring often brings a stronger wildflower bloom in the burned area.

Past Burns

Sonoma Ecology Center conducted successful prescribed burns on the Preserve in 2020 and 2021 that reduced Medusahead and other invasive species with support from ACR’s Fire Forward and the Good Fire Alliance.

  • Mother Nature’s gift of a cool morning, relative humidity, low wind plus our technically capable team and preparedness allowed Sonoma Ecology Center and our partners the right weather conditions to conduct another successful prescribed burn at Van Hoosear Wildflower Preserve last Friday. The video below, taken by Steven Lee, Senior Scientist and Research Program Manager, shows targeted sections and how well everything was managed.

    Executive Director, Richard Dale, had the honor of lighting the torch around 9:00 am, guided by our burn boss Phil Dye and many other partners monitoring the slow-moving flames. Overall about 11 acres were burned, in two segments, with a control line mowed around the entire area. Firefighters, fire-suppression trained volunteers, and engines moved ahead of the burn, wetting down the edges of the burn area, while more stayed behind the flames to ensure the fire stayed within the targeted area. Plumes of brown and light grey smoke rose until midday, when the flames died down. Crews patrolled the burn area for several more hours to assure the fire was truly out.

    There are tremendous restorative benefits in conducting prescribed burns. Visit our Prescribed Burns at Van Hoosear Wildflower Preserve page to learn more and read about 2020’s burn.

    Thank you to Phil Dye of Prometheus Fire Consulting for his leadership on the project and to our partners who made it possible. A big shout out to ACR’s Fire Forward team, the Good Fire Alliance, Sonoma Valley Fire District, Mayacamas Volunteer Fire Department, Cazadero Fire Department, and Santa Clara County Parks Department for contributing your support, equipment, and people. And kudos to the landowners, who understand what good fire can do.

  • Use of controlled or “prescribed” burns is both an ancient art and a new science. Here in the North Bay, the practice was used for centuries before the arrival of Europeans. Today, it is an essential tool in promoting both fire resiliency and biodiversity.

    That’s why we’re so pleased that the prescribed burn at Van Hoosear Wildflower Preserve on May 22 was such a success! The burn treated over 30 acres of grassland for noxious invasive species, leaving it primed for the Preserve’s famous wildflowers.

    Since 2004, we’ve worked with the Preserve’s owners to manage its meadows, grasslands, oak woodlands, and riparian habitats. It is our hope that the May 22 burn here in Sonoma Valley will be a model for future land management efforts in California grasslands.

    An action like this takes many trained hands and focused minds to come off successfully. We could not have done it without the expert help and enthusiastic support of our partners: Audubon Canyon Ranch’s Fire Forward program, Good Fire Alliance, Prometheus Fire Consulting, the Mendocino Volunteer Fire Department, Santa Clara Regional Parks, Sonoma Ag+Open Space and the Preserve’s owners. Thank you all!

Photos by Kristen Russell