Staring at Walls

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Staring at Walls: An Extended Hunt for the Elusive Rock Lady:

Digital Rasters and vector polygons once burnt my eye balls. Geological maps from the 1960s were scanned, digitized, exported to ArcGIS and georefrenced.

Maurandya petrophila is an odd life form. It is of the Scrophulariaceae family, kin to Monkey Flowers, Penstemons, Indian Paintbrushes, and the like. Rock Lady has dark green leaves covered by tiny silver hairs and edged with an irregular spikiness. It blooms sometime between April and July, exposing a cream colored flower with two striking yellow lines extending deep from from its throat.

Rock Lady grows only in small cracks on sheer walls of limestone. Exposed limestone is abundant in the many canyons of Death Valley, but Rock Lady does not grown on just any type of limestone. It only grows on dolomitic limestone, and more specifically only that from a few geological formations. Its favorite limestone seems to be that of the Lower Bonanza King geological formation, deposited over 500 million years ago. Though this formation is found in other mountain ranges inside and outside of the Park, the species remains endemic to the Southern Grapevine Mountains. Like most things about this odd plant species, the exact reason for Rock Lady’s small population numbers and tiny range is not fully understood.

Describing the Rock Lady species as “rare” is actually an understatement. In 1998, there were only 20 plants known to exist in the world, all located in one single canyon in the southern most portion of the twisted and rugged Grapevine Mountains.

This tiny size of this population in Titus Canyon, evoked great concern by the Death Valley park staff in 1998. Some even proposed closing the canyon completely to vehicles. Instead, interpretive signs were moved from one of the best known population centers in order to draw attention away from the plants.

The following spring, in 1999, two park volunteers performed an extensive survey of adjacent canyons in the Grapevine Mountains. Their work, along with that of a few Park employees, expanded Rock Lady’s range into two more canyons (Fall Canyon and another just to the north) and brought the total number of known individuals to 220.

Since 1999, little work was done to observe how the species was doing. In the spring of 2009, I attempted to locate all the known plant sites and recount them. Unfortunately, information on many of the locations of the plant populations was not clear or accurate and I was unable to find them all.

Last year, I counted only 120 living individuals. This year, on the other hand, with renewed effort and focus, I was able to relocate all known sites as well as survey in many new areas. This accomplishment came thanks to the help of several NPS employees and volunteers, who assisted me on all but one of my trips deep into the Grapevine Mountains.

The 2010 surveying and monitoring work was very successful and quadrupled the total number of known living Rock Lady plants to 755. Some of this large increase was evidently due to very wet and cool spring, but more than half of all the plants counted were found in places that were never surveyed before.

Aside from simply counting the plants this year, each population was more accurately mapped with GPS data and extensively photographed in order to make monitoring the populations more easily in the future and keeping better tabs on their health.

Though 755 is still an incredibly small number of plants, it is a massive increase from the 220 known ten years ago. With the new knowledge of Rock Lady populations gained in 2010 we can have slightly more confidence that some small disturbance will not drive the species to extinction and Rocky Lady, at least for little while longer. will continue her strange discrete existence in the deep canyons of the Grapevine Mountains.

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Comments

[Mike Morrison]

Very Cool Steve
Nice job dude, it sounds like you have grown into your job at Death Valley NP. We should try to catch up sometime soon. Mike Morrison

[Lorraine]

Great job!
Very interesting reading the story and looking at the pictures of that plant - nice work

[eric in pdx]

Nice work
Beautiful story, Steve. I am heartened to know you are out there counting and walking and taking care of DV.