Article

Plant Community Monitoring in the San Francisco Bay Area

A grassland plant community in Pinnacles National Park
A grassland plant community in Pinnacles National Park

NPS / Robert Steers

Map showing that plant community surveys occur in PINN, PORE, GOGA, MUWO, and John Muir NHS.

Why Are Plant Communities Important?

Plant communities create essential habitat for plants and animals. In the San Francisco Bay Area national parks, plant communities provide habitat for more than 160 special status species, from the federally endangered San Francisco garter snake to the endangered Sonoma spineflower. Plant communities are also integral to the functioning of many important ecosystem processes such as carbon storage, the water cycle, and fire regimes.

While several National Park Service projects have included limited forms of vegetation sampling for some time, a recently updated protocol guides comprehensive, long-term plant community monitoring.

Redwood forest in Muir Woods National Monument
Redwood forest in Muir Woods National Monument.

NPS /  Jessica Weinberg McClosky

Why Do We Monitor Plant Communities?

  • To establish baseline conditions for a diversity of plant communities
  • To detect changes in plant community structure and species composition over time relative to present-day baseline conditions
  • To identify trends in plant health and mortality, woody debris density (potential fuel for fires), invasive plant abundance, and soil cover (leaf litter, etc.)

How Will We Use the Monitoring Data?

  • To learn basic community dynamics (succession, variability, etc.), and to relate vegetation changes to changes in climate, land use, and biological interactions
  • To guide management decisions related to habitat restoration and species conservation for special status plants and animals
  • To inform strategies for responding to natural and man-made disturbances like fires, disease outbreaks, invasive species infestations, and climate change
Coastal dune vegetation on hillside at Point Reyes National Seashore.
Coastal dune vegetation at Point Reyes National Seashore.

NPS / Robert Steers

What Have We Learned?

Pilot data from 2011-2013 helped refine the methods and logistics for long-term plant community monitoring, and formal monitoring began in 2015. Researchers report the status of monitored plant communities after each year, and analyze the data for any changes or trends after a series of samples (with re-sampling planned for every three years).

For More Information

San Francisco Bay Area Network Botanist
Kelsey Songer

Links
San Francisco Bay Area Inventory & Monitoring Network
Pacific Coast Science and Learning Center

Summary by Jessica Weinberg McClosky, January 2014.
Download PDF from the NPS Data Store

Tags

Golden Gate National Recreation Area, John Muir National Historic Site, Muir Woods National Monument, Pinnacles National Park, Point Reyes National Seashore

Last updated: April 11, 2023