Federal Listing of rare plants in California has been in a log-jam for over a decade. Over the last dozen years, only three plants have been added to protection under the Endangered Species Act. The 1990s was a period when listing activity increased dramatically. Over the past dozen years, listing has remained essentially static. Endangerment threats to the California flora have been increasing over this period.
The recent, August 2013, proposal to list Ivesia webberi is the most recent activity. Listing of this single taxon does not break the jam. It actually just highlights a dozen year moratorium – a fact that in practice demonstrates that listing actions are a political and not a biological process.
On a biological basis, perhaps something on the order of 400 species of California plants quality for Federal listing, about twice the number presently listed.