Missimer Snell Valley Preserve

Located in Snell Valley, Napa County, this preserve is renowned for its vibrant spring wildflower displays within the rare serpentine grassland habitat.

Ecological Significance

The preserve’s serpentine meadows are among the most important botanical sites in Napa County and the Bay Area. Serpentine soils, characterized by high heavy metal content and low nutrient levels, support a unique assemblage of plant species adapted to these challenging conditions.

Home to over 290 native plant species—representing nearly a quarter of all known native species in Napa County, exceptional for a 240 acre area. —the preserve includes several listed as threatened or endangered by the California Native Plant Society, such as:

• Narrow-Leaved Daisy (Erigeron angustatus)
• Napa Western Flax (Hesperolinon sp.)
• Colusa Layia (Layia septentrionalis)

These species contribute to the preserve’s reputation as a botanical gem of the North Coast Ranges.

Historical Background

The preservation of Mead Ranch builds on a legacy of land conservation rooted in the vision and generosity of Dale and Sue Missimer. In 1999, the Missimers made a transformative gift to the Land Trust, establishing the Missimer Preserve to protect the native wildflowers, plant communities, and riparian corridors they deeply valued. Their dedication to safeguarding Napa Valley’s natural heritage laid the foundation for long-term ecological stewardship in the region.

This commitment to conservation continues with the expansion of the Preserve as recently as 2022, further strengthening the network of protected lands in this exceptionally biodiverse area.

Wildflower Displays

Each spring, the preserve transforms into a vibrant tapestry of wildflowers, attracting enthusiasts from across the region. The serpentine grasslands burst into color, showcasing species such as the Yellow mariposa lily (Calochortus luteus), among others. It has become an annual pilgrimage site for wildflower enthusiasts from throughout the region. Snell Valley and the surrounding hills are exceptional for their almost complete lack of development. The entire viewshed from Snell Peak is a mosaic of wildlands and pasture, a visual treasure.

Conservation and Stewardship Efforts

Since 2013, the Land Trust has led focused, science-based stewardship efforts at the preserve to protect and restore its exceptional native plant communities. These efforts are especially critical in the preserve’s serpentine meadows—rare and sensitive habitats known for supporting a rich diversity of endemic wildflowers and plants.

A cornerstone of our management strategy has been the removal of invasive species, which threaten the ecological balance and outcompete native vegetation. To address this, the Land Trust employs a multi-faceted approach that includes:

• Prescribed Burns: Carefully planned and implemented controlled burns have proven highly effective in managing invasive species and stimulating the resurgence of native plants. These burns mimic natural fire cycles that many native species have adapted to, and in the seasons following, they often lead to breathtaking wildflower blooms.
• Invasive Species Removal: The Land Trust works with the American Conservation Experience (ACE), and crews are deployed to hand-pull invasive plants in sensitive areas where mechanical removal is not feasible. This hands-on work is crucial in maintaining the health of the preserve’s unique plant communities.
• Scientific Research and Monitoring: Ongoing ecological monitoring and research guide our management decisions, ensuring that each intervention is rooted in evidence and supports long-term ecosystem health. Tracking changes in plant populations and conditions helps us evaluate the effectiveness of our efforts and adapt as needed.

By combining traditional land stewardship practices with modern conservation science, the Land Trust is ensuring that the Preserve continues to thrive—providing critical habitat for native flora and fauna.

Read more about our ongoing stewardship efforts—like controlled burns and invasive species removal—on our blog.

Public Access and Engagement

Access to the Missimer Snell Valley Wildflower Preserve is by permission only and through guided hikes organized by the Land Trust. This approach ensures the protection of sensitive habitats, nesting sites, and rare plants while allowing visitors to experience the preserve’s natural beauty and ecological importance.

The Missimer Snell Valley Wildflower Preserve exemplifies the Land Trust’s commitment to preserving Napa County’s natural heritage. Through careful stewardship, this preserve remains a sanctuary for rare plant species and a source of inspiration for wildflower enthusiasts and nature lovers alike.