“Rushing” Native Plant Restoration at Lower Crystal Springs Dam

“This is a big deal for us,” said Mia Ingolia, SFPUC Senior Biologist.

Like proud parents, SFPUC Natural Resources and Lands Management staff gazed down upon hundreds of newly-planted green shoots on the banks of San Mateo Creek. The adoration is absolutely deserved. These are the first plants grown at the Sunol Native Plant Nursery to be placed in the ground in a wildland watershed setting. 

The SFPUC owns and manages two Bay Area watersheds as part of its Regional Water System. SFPUC Natural Resources and Lands Management staff historically used native nursery plants for projects within the SFPUC’s watershed lands. However, after inadvertently introducing plant pathogens into the watersheds, staff realized that it was very difficult to find disease-free plants that do not pose a threat to the vegetation in the watersheds. Healthy watersheds produce high-quality water and are resilient in times of fire or drought. In line with the principles of the SFPUC Environmental Stewardship Policy, the agency strives to maintain the ecological integrity of its watersheds for current and future generations.

Nursery intern Gonzalo Mannucci (left) and Senior Biologist Mia Ingolia (right) admire their handiwork.

Because the agency has a continuous need for healthy landscape plants at the Sunol Yard and future Watershed Center in the Alameda Creek Watershed, the SFPUC constructed the Sunol Native Plant Nursery using cutting-edge design specifications that exclude plant pathogens to the best extent possible. Dedicated nursery staff follow best management practices that operate more like a laboratory than a nursery.

“The process we follow at the nursery is a process that values diligence and thoroughness over speed and ease,” noted intern Gonzalo Mannucci. “Seeing these plants in the ground validates the hard work we do day in and day out at the nursery.”

These plants, which resemble grasses but are called rushes, started their lives as seeds collected in the Alameda Watershed, and they were sown into containers at the Sunol Native Plant Nursery over a year ago. They were intended for use as landscaping at the newly-constructed Sunol Yard. Staff grew and planted 20,000 plants for the Sunol Yard project, and those plants are already in the ground and thriving. So how did these East Bay plants end up in San Mateo Creek on the Peninsula?  Serendipity and lucky timing.

The newly-planted rushes in their first-ever natural setting. 

“One of the things about this species of rush is that it has incredibly small seeds,” said Mia Ingolia.  “When we were planting for the Yard, the flats were over sown because it was hard to know how many seeds you actually planted. We ended up with excess plants.” The Lower Crystal Springs Stilling Basin Connecting Channel Project had an urgent need for some native plants to place along the San Mateo Creek Channel adjacent to the dam’s stilling basin. Nursery staff had no trouble making the excess 4,000 rushes field-ready quickly. 

Staff at the Sunol Native Plant Nursery will next swivel to focus on growing plants for the future Alameda Creek Watershed Center and on seed amplification (seed production) projects for rare and endangered plants. Natural Resources and Lands Management Biologist Scott Simono explains it this way. “Let’s say we collect 20 seeds from an endangered plant, which turn into 20 plants at the nursery. Let’s pretend that each plant produces 150 seeds. Soon we will have thousands and thousands of seeds that we can use to grow more plants in the future.”

The stilling basin at Lower Crystal Springs Dam.

These efforts also teach the SFPUC more about these rare plants, many of which have never been grown in a nursery setting. Knowing what makes native plants happy and thriving will inform future restoration efforts and insure their success. 

Just like the rushes at the Lower Crystal Springs Dam stilling basin.