Cheadle Center for Biodiversity and Ecological Restoration

UC Santa Barbara’s Cheadle Center for Biodiversity and Ecological Restoration(Cheadle Center) began working with the US Fish and Wildlife Service to plan for theintroduction of the federally-endangered Ventura marsh milk-vetch (Astragalus pycnostachyus var. lanosissimus) at UCSB’s North Campus Open Space (NCOS) in 2018. The first individuals were planted in a sandy site with high sub-surface soil moisture on the upper edge of the highwater mark of the newly restored upper arm of Devereux Slough in November 2019. These individuals were grown from seed collected from the original population in Oxnard and obtainedfrom Mary Carroll. In an effort to elevate plants during episodes when the slough is fully ponded and to mimic conditions we believed may be related to success at planted locations in Ventura five east-west trending berms approximately 1.5 meters wide, 0.5 meters tall, and 10 meters long were constructed with a small tractor. These were to test the effect of subtle differences between north and south facing slopes as was observed in Ventura. At the same time, 6 vetch were outplanted in the “EEM” Swale, a willow woodland with sandy soils near an ephemeral stream. In November 2019, 231 (Sandy zone) and 6 other individuals, grown at the Cheadle Center nursery and about 10 months old, were planted, with subsequent planting taking placeon adjacent sandy mounds in September 2020 (55) and October 2020 (46) (Figure 1). Theseare detailed in previous reports.

In December 2020, an estimated five cups of unprocessed seed were collected from themain population of previously planted individuals and dispersed experimentally across different zones of NCOS that were seen as potentially suitable habitat for the expansion of this initial population (Figure 1). The “sandy zone” is a northeast-facing slope and adjacent sandy plain just southeast of the main planted population and consists of recently exposed soils with a similar consistency and make up of fine beach sand. The “Tule Seep” is a perennially wet seepsurrounded by willow (Salix lasiolepis) and tule (Shoenoplectus californicus) and underlain byclay and clay loam soils. Whittier Pond is a small freshwater pond that holds water throughout the entire year. The “Bioswale” site is a string of low-lying swales or subtle vernal pools descending in elevation northwest from the mesa into the saltmarsh transition with dense clay soils. Finally, several square meter plots were seeded in South Parcel on sandy soils, in mixed riparian woodland and coastal sage habitats. Each of these five zones received one cup of collected seed and fruit material. Germinating seedlings were observed and monitored on a monthly basis during the growing season over the past 3 years.