as a perfect "common garden" study, to detect genetic variations within the population. See also California coastal prairie References External links CalFlora Datatabase: Holocarpha macradenia (Santa Cruz tarweed) Jepson Flora Project — Holocarpha macradenia USDA Plants Profile for Holocarpha macradenia (Santa Cruz tarweed) Holocarpha macradenia — U.C. Photo gallery Madieae Endemic flora of California Natural history of Alameda County, California Natural history of Contra Costa County, California Natural history of Marin County, California Natural history of Monterey County, California Natural history of Santa Cruz County, California Threatened flora of California Plants described in 1836