Which Rare Plant Survey Is Right for Your Project?
As the rainy season winds down and temperatures begin to warm, it is time to start planning botanical surveys for upcoming projects. Rare plant surveys are typically conducted to identify the locations of special-status plant species so that they can be avoided during project design or mitigated if impacts cannot be avoided.
These surveys may occur during early pre-project assessments to identify potential biological constraints, or they may be required prior to project implementation as part of a resource agency permit or the California Environmental Quality Act (CEQA) process. Timing is critical. Surveys are generally conducted when plants are in bloom, since this is when they are most easily identifiable and when surveys are considered valid by regulatory agencies.
Most rare plant surveys occur between March and June, although additional surveys may be necessary for species that bloom earlier or later in the season. Some plants have very short blooming periods, which narrow the survey window and requires careful planning to ensure species are not missed.
Special-status plants may receive regulatory protection through several state and federal laws, including the Federal Endangered Species Act (ESA), the California Endangered Species Act (CESA), and the California Native Plant Protection Act (NPPA). In addition, the California Native Plant Society (CNPS) maintains the Rare Plant Inventory, which assigns rare ranks to plants. Species with these rankings are generally considered special-status under CEQA. Some species may also be designated as sensitive under local plans and policies.
Survey requirements can vary depending on the species and the applicable regulatory standards. The U.S. Fish and Wildlife Service and the California Department of Fish and Wildlife each maintain specific protocols for surveys targeting federally and state-listed species. In some regions, these requirements are even more specific. For example, the Santa Rosa Plain, in and around the City of Santa Rosa, has established guidelines for federally listed plants that require two years of surveys with three site visits per year.
In other cases, survey requirements may be less intensive. Some sites are known to support species that require only a single, well-timed survey, while other sites or habitats may have little or no potential to support rare plants at all. Determining the appropriate survey approach usually begins with a desktop evaluation and, in some cases, a short site visit.
Because of the many regulations, survey standards, and species-specific protocols, determining the right survey approach for a project can be challenging. Survey timing can also be critical, particularly when project schedules depend on completing surveys within narrow seasonal windows.
WRA has decades of experience helping clients plan and implement rare plant surveys throughout California. Our team works closely with project partners to determine the appropriate survey approach, navigate regulatory requirements, and keep projects moving forward. Contact us to learn more about how we can support your botanical survey needs!