Before & After: Conservation Grazing on the Flats

Andrew Evans steps over the single-wire fence into the San Francisquito Flats pasture. Photo by Alix Soliman.

September 7, 2022

By Andrew Evans, Conservation Grazing Associate

Eating an estimated 1,051,200 pounds of forage each year, the Conservancy’s herd of cattle manages disturbance in The Preserve’s prairie ecosystems across a 2,800-acre footprint. Adapted to fire, our grasslands need disturbance to remove crowding thatch, cycle nutrients, and sustain year-to-year ecosystem productivity. 

As the seasons change, we see green grass grow and then crisp back up to a golden yellow again. It can be difficult to remember what, exactly, a particular site looked like just a year before. To supplement our rigorous exclosure monitoring protocol in gauging our ecological impact and progress in our pastures, we use photos to compare exact locations before, during, and after the cows move through. 

At the heart of The Preserve, our pastures in the flats (including San Francisquito Flats, Trail Horse Pasture, Chicken Flats, and Downtown) are our most heavily trafficked grasslands with Chamisal Pass and Rancho San Carlos Road running through them.

 San Francisquito Flats

BEFORE (December 2021): In what used to be a seasonally-flooded wetland, historic ranching operations dug a trench through and drained the San Francisquito Flats to seed and harvest the now-invasive harding grass (Phalaris aquatica).

AFTER (March 2022): In an effort to remediate this inherited legacy, our Conservation Grazing Program intentionally grazes the flats longer than other areas to sufficiently clear the harding grass canopy so native species can grow with the next rains.

Trail Horse Pasture

BEFORE (March 2022): Across the road from The Preserve’s Equestrian Center, our “Trail Horse Pasture” is a wet meadow that is lush with native species like creeping wild rye (Elymus triticoides) and mexican rush (Juncus mexicanus). However, even in areas with productive native species, buildup up dead plant matter begins to inhibit future growth.

AFTER (March 2022): Our Conservation Grazing Program grazed this pasture to break up the thatch and provide a cleared canopy to stimulate the native species’ recovery. In these photos, our herd grazed this pasture in March 2022, with the follow-up image being taken the day after the herd was removed.

Chicken Flats

BEFORE (December 2021): As a functioning wet meadow, the Chicken Flats is one of the Preserves few remaining seasonal wetlands. With native California buttercup (Ranunculus californicus), brown headed rush (Juncus phaeocephalus), and Danthonia californica competing with invasive Harding grass and tall fescue (Festuca arundinacea), our cattle herd helps mediate that competition to give our native species a fighting chance.

AFTER (March 2022): Collaborating with the Conservancy’s Restoration, Science, and Climate Change Adaptation programs, our grazing team is working to adjust our grazing to better-address our sensitive wetland-dependent plants and animals. In these photos, our herd grazed the Chicken Flats in late December of 2021, with the follow-up photo taken March of 2022.

Downtown

BEFORE (March 2022): Named for its intersection of Preserve homelands, Conservancy wildlands, the Sports Club, and Equestrian Center, our “Downtown” pasture provides a savanna transition zone between thick oak forest and grassy wetlands.

AFTER (March 2022): With the collaboration of lot owners, our grazing team was able to manage the harding grass and velvet grass (Holcus lanatus) that has invaded this pasture’s wetland zones, all the while clearing away plant canopy for resident squirrels (who prefer clear lines of sight) and diverse native wildflowers including popcorn flower (Plagiobothrys nothofulvus), lupine (Lupinus nanus) and tarweed (Madia elegans). In these photos, our cattle grazed these Openlands in early March of 2022 and the follow-up photo was taken two weeks later.

With almost 10 years of conservation grazing experience, the Conservancy serves as a resource for landowners and organizations seeking to manage their grasslands for ecological health. For more information about our Conservation Grazing Program, please contact our Conservation Grazing Program Manager Claudio Núñez at cnunez@slconservancy.org.