Large-flowered fiddleneck (Amsinckia grandiflora) is a critically endangered plant species that is a California endemic wildflower presumed extant as only two small natural populations. In partnership with the University of California Botanical Garden as a subcontractor, VNLC is oversaw this federally funded project to propagate and reintroduce the species into its historic range at 10 suitable sites, and was responsible for the study design, analysis, and implementation. Sites were selected through remote sensing and ground surveys that best match the habitat of the existing population. This includes a presumed historical range within eastern Contra Costa, Alameda, and western San Joaquin Counties, at elevations ranging from 800 to 1,800 feet above sea level (244 to 550 meters). The species occupies a very narrow ecological niche characterized as transitional grassland habitats on very steep, primarily north-facing and well-shaded hill slopes, with moist, rich clay or clay-loam soils.
The project was carried out between 2012 and 2021, during which time four new self-sustaining populations of the species have been established. Two of these have merged together to form the largest population of the species—more than four times the size of the largest natural population. Previous efforts by other teams of ecologists were carried out over a period of more than 30 years, none of which were successful.