Rare Plant Treasure Hunt

Several years ago Rancho Santa Ana Botanic Garden (RSABG) teamed up with the California Native Plant Society (CNPS) through a contract grant from the Bureau of Land Management (BLM) and the Department of Fish and Wildlife to do rare plant surveys across California deserts as part of the Rare Plant Treasure Hunt (RPTH) program. Last year marked the third year for RPTH, a program created and named by Josie Crowford of CNPS.

A Rare Plant Tresature Hunt group travels out to Castle Peaks. Photo: Kim Clark

It is largely a citizen-science program with the goal of getting volunteers out in the field to experience California wild places and assist in rare plant surveys. These surveys largely target rare plant populations that haven’t been revisited in more than 20 years in order to evaluate the current status of these populations.

Many people may be under the impression that the desert is nothing rocks, lizards and an occasional spiny plant—an open wasteland to be crossed to get to Las Vegas or Lake Havasu. But California deserts hold more than 35 percent of the flora of California and have some of the areas of highest diversity for the state. There are many botanically unexplored mountain ranges and valleys out there. In 2012 alone, there were five plant species found in California deserts new to science described by RSABG scientists and researchers.

The Rare Plant Treasure Hunt program largely focuses on the California deserts often associated with the development of renewable energy projects. There are currently thousands of acres proposed for possible development, of which a great deal has had little botanical exploration.

It is the goal of the RPTH program to get volunteers out to these places to experience them first hand and to educate others on California’s diverse flora and the importance of its conservation.

Coryphantha alversonni in the Big Marias Mountains. Photo: Kim Clark.

Volunteers from the Sierra Club, the Desert Survivors Organizations, HabitatWorks, The Wildlands Conservancy, CNPS chapters and subchapters from across California have often participated with Rancho Santa Ana Botanic Garden in the Rare Plant Treasure Hunt. But many volunteers were not affiliated with any particular organization, but were just interested in joining the group to explore and learn about the desert and to have a personal experience with these wild places while doing so.

The spring field season in 2012 was one of the driest years on record for the California deserts; most areas got only 0.01 millimeters of rain or absolutely no rain at all. Watching the doppler in the winter of 2011-12 was often like watching a blank screen as there was so little weather action. Watching the weather stations and dopplers frequently helps plant scientists predict which areas may have germination or bloom. But even in dry years, the desert rarely disappoints and almost every area visited had at least one rare plant population if not dozens.

The summer field season seemed to the opposite as some parts of the California deserts received the most summer rain they have received in more than a decade. The eastern Mojave in particular had an amazing summer bloom and RSABG/RPTH participants were able to document around 100 rare plant populations on just a few trips.

A total of 24 trips were made in 2012. These trips ranged from day trips to three-day excursions into very remote places. We started in March at below sea level around the Salton Sea, topped out on Southern California’s highest peak on Mount San Gorgonio at 11,500 feet in July, and then headed back down to the lower elevations following the summer monsoonal storms in September. We documented around 300 rare plant populations. Many of these were newly documented. We trekked into the Panamint Mountains and found the type locality of the Panamint daisy (Enceliopsis covillei), which is the plant that has always adorned, and will continue to adorn, the CNPS logo; this population had not been revisited since Frederick Coville made the first collection of this plant in 1891 on the Death Valley expedition. The new species was later named for him. We found the first population of Abrams spurge (Chamaesyce abramsiana) in Imperial County in 100 years; all historic populations from Imperial County are likely extirpated due to development and agriculture. We documented many range extensions of rare plants, locating populations where they had never been found before. We provided information that aided in the evaluation of plant species for the CNPS inventory, including information about its abundance (or lack thereof!) in California and about threats to historic occurrences of a given species. We had many wonderful treks into some amazing places and spent many nights under star filled skies. All in all, it was a very successful and productive year.

If you would like to learn more about the Rare Plant Treasure Hunt program please visit the Rare Plant Treasure Hunt Website.