Rare Plant Treasure Hunt Update: the CNPS De-Extinction Project

In early May, a team from the Rare Plant Program went down into the urban wilds of the greater Los Angeles area in search of plants presumed to be extinct. Amidst the piles of trash, stealthy homeless encampments, fields of invasive weeds, cookie-cutter stucco houses, and mining lands, it could seem like a search for a needle in an inhospitable haystack. Yet, the CNPS De-extinction Project is far from that.

Conceived in 2015, the goal of the De-extinction Project is to locate populations of plants that have not been seen in many years, whose habitats may have been significantly altered or destroyed, and now have been given a California Rare Plant Rank of 1A in the CNPS Rare Plant Inventory (Plants Presumed Extirpated in California and either Rare or Extinct Elsewhere). These plants are only presumed to be extinct, as some factors— such as the viability span of the seed bank for a particular plant and the vicissitudes of weather patterns over time—contribute to the possibility of regrowth and thus, rediscovery. There is also simply a lot of ground to cover to effectively search for these plants in possible habitats so that locating these plants can become an issue of sheer person power available for the search, as well as good old-fashioned luck!

CNPS is no stranger to rediscovery. In 2009, our Executive Director Dan Gluesencamp rediscovered the Franciscan manzanita (Arctostaphylos franciscana) on a traffic island near the Golden Gate Bridge. In 2016, Steve Schoenig, currently a Rare Plant Treasure Hunt (RPTH) volunteer and former Coordinator of the RPTH, rediscovered the Serpentine Canyon monkeyflower (Erythranthe pericaulis) deep in the heart of the Plumas National Forest. In the early days of the CNPS Rare Plant Inventory, rediscoveries were more common as the Inventory itself helped catalog which plants most needed searching for. Over the years, as more habitat has been destroyed, rediscovery has become less common and the need to fine tune our searches more essential. Once a species is rediscovered, our state has another chance to conserve and protect it, and the plant will often be given a ranking of 1B.1—rare in all of its range and still vulnerable to the highest degree of threats.

In order to enhance our chances of locating these plants, CNPS Rare Plant Botanist Aaron Sims did extensive research on the historical occurrences of all 1A plants in the Inventory as of 2015. He did analyses of which plants were the most likely to be found, based on factors including intactness of habitat near or around historical occurrences as well as dates last seen, and created a prioritized list of targets for rediscovery. With each plant target, Sims also generated exact locations around which to centralize our search, concentrating our resources to focus on the greatest possibility of success.

With this data in hand and more than just a little hopefulness, Rare Plant Program botanists scoured several sites in the greater L.A. area for two 1A plants the second week of May. We can’t divulge details of the outcome just yet, but the hunt was successful in many ways. Several areas of semi-intact habitat were found for these species, despite the ubiquitous sprawl. We will report back as soon as we know more.

The CNPS De-extinction Project is currently seeking out other 1A plants in other areas of the state. We also hope to return to the L.A. area throughout the summer to continue our search for these plants and deepen our search to include other elusive plants presumed to be gone in this densely-developed place. Interested to join in the hunt? Let us know by sending us an email!

Catherine Curley, Assistant Botanist/Rare Plant Treasure Hunt Coordinator