The Vascular Flora of Plum Canyon, Anza-Borrego Desert State Park
Larry Hendrickson, Tom Chester, James Dillane and Kate Harper
The "plums" of Plum Canyon are actually desert apricot, Prunus fremontii. Picture taken at the parking area at the end of the dirt road up Plum Canyon on 12 December 2012, of plants leafed out following monsoonal rain in August 2012. Most of the year the plants are leafless. Click on the picture to get a larger version.
Google Earth View
Procedure For Compiling The Checklist
Plum Canyon is a delightful canyon in the western part of Anza-Borrego Desert State Park. It is the first major canyon on the right (south) seen by people traveling from western San Diego County as they leave Sentenac Gorge and emerge into the desert proper. These eastbound travelers usually notice the showy red blossoms of chuparosa, Justicia californica, for the first time where Plum Canyon wash meets Highway 78 (SR78), where the first large population occurs.
As a result of its location in the Desert Transition Zone, Plum Canyon has an interesting collection of species, with good diversity. The plant checklist below contains 175 taxa, which range from lower desert species to even a few coastal species. The Canyon contains the westernmost extent at this latitude of some desert species, such as Carlowrightia arizonica, Arizona carlowrightia, and the easternmost extent of some coastal species, such as Selaginella bigelovii, Bigelow's spike-moss.
Even better, this Canyon has few non-native species. There are only four non-native species in its plant list (five if you count the possible non-native Mollugo cerviana), and they are not very abundant in the canyon. The biggest scourge of the desert, Brassica tournefortii, Asian mustard, is only found along SR78 at the bottom of Plum Canyon Wash. An aggressive weeding campaign led by the first author has kept this species mostly out of Plum Canyon.
The origin of the name Plum Canyon is not known for certain, but it is most likely to come from the abundant desert apricot, Prunus fremontii, in the canyon. Cultivated plums and apricots are very closely related, both in the genus Prunus, distinguished in Bailey as follows:C. Fruit glabrous, usually with a slender pedicel that remains with it, the stone not prominently furrowed ... Plums
CC. Fruit pubescent, the pedicel short and separating at maturity, the stone usually furrowed on the margin... Apricots
Prunus fremontii has pubescent (= very short hairy) fruit, which clearly makes it an apricot, not a plum. But perhaps someone thought the dark color of the fruit at times was closer to a plum, and named the canyon for that.
This canyon is a favorite place for CNPS plant tours led by the first author; see photos from the March 2011 trip.
The entrance to Plum Canyon is 4.1 miles east of Scissors Crossing, and 2.7 miles west of the turnoff to Tamarisk Grove Campground and Yaqui Pass Road (S3).
Most passenger cars can easily drive the 1.6 miles up the sandy non-paved road from SR78 to a parking area where the canyon walls close in, preventing further car travel up the canyon (take the right-hand fork at mile 1.35). A fairly easy ~3 mile roundtrip, with 400 feet of elevation gain, walk up the canyon along the California Riding and Hiking Trail leads to a saddle overlooking Earthquake / Shelter Valley.
An even more interesting botanical trip is to start walking at SR78, to experience the full transition from the lower-elevation desert proper to the lower part of the desert transition zone near the top of the canyon. That walk is roughly 6 miles roundtrip with 900 feet of elevation gain, from 1700 feet to 2600 feet.
For botanists, one of the things that makes the walk along the entire canyon / wash special is that one is following the footsteps of California's first botanist, Willis Linn Jepson, the "Botany Man", who wrote the first manual on the flora of California.
Lower Plum Canyon was called Wagon Wash in those days, and was part of the wagon route from Earthquake / Shelter Valley to Yaqui Well. The old route heading west branched at the top of Plum Canyon; the California Riding and Hiking Trail follows one of the branches south from Upper Plum Canyon to North Pinyon Mountain Road in Earthquake / Shelter Valley. The other branch headed west down to the Sentenac Cienega area. (see map of Wagon Wash; Wray 2004 The Historic Backcountry: A geographic Guide to the Historic Places of the San Diego County Mountains and the Colorado Desert; and the 1913 topo map with the vegetation mapping showing the routes.
Today it seems like this route could never have been passable by wagons in some places. However, at least some of the rockslides creating impassable stretches appear fresh, and may have occurred after the wagon route was abandoned. In fact, the construction of the wagon route may have precipitated at least some of these rockslides by undercutting the slopes.
There is at least one area of upper Plum Canyon where the trace of the old wagon road is still visible, on the stretch just below the saddle (see also version with the old wagon road marked).
See Road Timeline in the Borrego Desert Area for dates of road construction that bypassed this Wagon Road.
Some links to photographs of Plum Canyon and its plant species:
- Keir Morse's 259 photographs from Plum Canyon on 5 March 2011.
- Keir Morse's 305 photographs from the canyon immediately east of Plum Canyon on 27 March 2011
- James Soe Nyun March 2011
- Kim Davis and Mike Stangeland 16 March 2010 including a beautiful photo of the canyon itself.
- Narca Moore-Craig March 11, 2011
- John and Evelyn Boucher 17 April 2010
- Doug Taron December 03, 2008
Google Earth View
Google Earth View of Plum Canyon and points east as seen using a vantage point at 6000 feet elevation from just south of Scissors Crossing looking northeast. Some features are labeled (see text below). The North direction is indicated in the upper right corner. Click on the picture to get a larger version. See also unlabeled version.
In the Google Earth View, the Plum Canyon drainage is outlined in red, with two saddles on the ridgeline dividing it from Earthquake / Shelter Valley shown in red diamonds. Blue lines show our survey routes on 12 and 21 December 2012. The northernmost route corresponds to the old Wagon Road built by John McCain sometime after 1895 and prior to 1913, which was only superceded in 1922 when SR78 was finished through Sentenac Gorge. Many traces of the old Wagon Road are still visible along most of its route on the Sentenac Cienega side of the Plum Canyon Saddle, but only a few traces are visible on the hike from the Plum Canyon Parking Area to the northernmost saddle.
The short Plum Canyon hike from the Parking Area goes to the northernmost of the two saddles shown on the map. However, there are no signs telling the hiker when to exit the main canyon in order to reach it. As a result, many hikers end up continuing up the main wash in a direction away from the saddle overlooking Earthquake / Shelter Valley! Or they take the California Riding and Hiking Trail to the southwest ridgeline of Plum Canyon. Or if the first turnoff is missed, but the second turnoff is taken, hikers end up at the southern of the two saddles shown on the map, which is just a bit longer.
Willis Linn Jepson's Comments
As mentioned above, one of the botanical highlights is being in an area where Jepson himself collected 72 vouchers in 1920 and 1928. His fairly extensive notes in his field books, along with his vouchers, reveal what it was like 85 and 93 years ago. After our next survey in prime time, to make our observed list more complete, we'll do a detailed comparison of what we see now to conditions nearly a century earlier (see also below).
Jepson collected 72 vouchers from Wagon Wash in April 1920 and April 1928. His Field Books that describe the area, including the geography, plants and animals, and his collections, are all online:
- 1920 (vol. 37, pages 143-145, 147, 151, 157; collections #8766 to 8950), including a map of Wagon Wash, and
- 1928 (vol. 46, pages 193-214; collections #12,463 to 12,539).
In the Field Book pages, click on the upper right arrow to "turn the pages" in his field book. There are links to the online page for each of his vouchers that usually give a more-current name for each voucher. We've transcribed some of his pages; click on the link at the bottom of the pages when you see Read transcription. If you don't see that link, we encourage you to transcribe a page or two.
Jepson's description of Plum Canyon = Wagon Wash from 1920 is still an accurate overview today:This wash, from its junction with the San Felipe region to the summit of the pass is about 2 3/4 miles. The lowest half mile is Smoke Bush (Dalea spinosa = Psorothamnus spinosus), very much scattered. The next 1 1/2 miles is Hyptis emoryi which is very abundant and gives a distinct character to this part of the wash. The next half-mile is Desert Apricot (no. 8769; Prunus fremontii) which is abundant; the last 1/8 mile is no. 8772, Coleogyne ramosissima, dominant at very summit; but not extending down far. The 1/8 mile below it is most interesting for the Bernardia (no. 8775). [vol. 37, p. 157]
Jepson's notebook has Ayenia instead of Bernardia, but his voucher is determined as Bernardia, which is indeed an interesting species at that point in the Canyon today. We have not yet found any Ayenia at that point in Plum Canyon.
When Jepson said not extending down far for the Coleogyne ramosissima, he meant within Plum Canyon, on the east side of the summit, since that species extends all the way down to Sentenac Cienega on the west side of the summit.
And Jepson's admonition that desert botany requires careful scrutiny is just as valid today:Many things show only a single individual, so far as we notice. For example, only one individual of Cassia armata Wats. was found. The desert, therefore, requires careful scrutiny - all the more in that certain things are everywhere so omnipresent. It is, too, easy to walk over inconspicuous plants in the desert sands, such as Nemacladus, no. 12,486. [vol. 37, p. 202]
Even in 1920 Erodium cicutarium, redstem filaree, was a problem. (In fact, the earliest botanists to explore California often found it.) Jepson commented:I have not mentioned Erodium cicutarium this trip very much but everywhere in the desert one finds it. When the sandy granite is very dry it covers the country with small plants; even where desert plants (annuals) do not get along well. [vol. 37, pp. 152-153.]
Jepson clearly enjoyed Plum Canyon. In 1928 he wrote:We move down the next day, Apr. 20, through Sentenac Canon, and turn up, off the road, into the lower part of the Wagon Wash, a hundred yards or more, and make camp. It is still very windy but we spend the day botanizing in the wash. In this locality I collect nos. 12,473 to 12,510. We spend the day and night here. It is a fine camp in a fine country for botanizing. [vol. 46, pages 195-196]
One big difference from 1928 is that we have not yet found Eriogonum plumatella in Plum Canyon. Jepson wrote:There is a great deal of this in the wash called Wagon Wash. It forms colonies and makes a marked stand in places where there is little other vegetation. It also grows as scattered individuals on the first bench above the wash (3 to 5 ft. higher) scattered amongst the creosote bushes and cacti in open places. [Jepson originally called this E. palmeri, but crossed the name out on p. 201 and replaced it with E. plumatella; vol. 46, p. 207]
In our surveys of the length of Plum Canyon on 12, 21, and 28 December 2012, and 2 January 2012, we found not a single individual of E. plumatella! Nor has the first author found any in his extensive explorations of this Canyon. We did find a single plant in the wash immediately east of Plum Canyon Wash, but none others in a 7 mile exploration of that wash and canyon.
It is possible that in 1928 Jepson was referring to San Felipe Wash in the vicinity of Plum Canyon. San Felipe Wash was probably the wagon route after descending Plum Canyon.
Other Botanical Highlights
- This canyon is the type locality for Nemacladus glanduliferus, from Jepson's collection #8766 from 24 April 1920 (Picture of voucher).
- This canyon is also the type locality for a variety of Prunus fremontii that is no longer recognized as being distinct from the rest of the species, var. pilulata, from Jepson's collection #8769 from 24 April 1920).
Jepson gave its distinguishing characteristics as:Leaves orbicular, more or less truncatish or subcordate at base, 5 to 8 lines [10 to 16 mm] long; fruit (immature) subglobose, a little flattened, a little broader than long, 4 lines [8 mm] long.
He gave the other variety as having larger leaves, 0.5 to 1.5 inches (13-38 mm) long; with oblong-ovoid or elliptic-ovoid fruit, 4-6 lines long. You can see why floras no longer accept var. pilulata, since there is a continuum between it and other plants of this species. We've noticed no difference in the size of the leaves of plants in Plum Canyon. It is likely that Jepson's sample just happened to be of a plant with smaller leaves than normal.
- This canyon has the easternmost population of Selaginella bigelovii in this latitude region of San Diego County, the Scissors Crossing area.
- This canyon is the only known location of Calyptridium parryi var. arizonicum in California (see a photograph of it from here). The first author collected this taxon here in two different years, on 16 April 2004 (#162) and 22 March 2008 (#2766) (see photograph of one voucher). As a result of these collections, it was one of the new taxa in the 2012 Second Edition Jepson Manual Treatment.
Note that the first collection of this taxon was only #162 of all his collections, showing you don't have to be a long-time collector in order to find something new for the flora of California!
The first author suspects that it might not be a coincidence that this Arizona taxon has appeared in Wagon Wash, given the amount of traffic from Arizona that must have occurred along this route in the past.
In fact, we know of two other species introduced in the vicinity of this area from points east:
- the Arizona long-horned devil's claw, Proboscidea parviflora ssp. parviflora, was introduced to the Banner Queen Ranch from a load of hay from Arizona in the mid-1980s.
- a waif of Crotalaria juncea, sunn hemp, was discovered growing in Sentenac Canyon by Kate Harper on our 12 December 2012 trip as she was driving through the gorge on the very day of our field work in Plum Canyon (we vouchered this plant, which had failed to produce any seeds). This single plant almost undoubtedly came from the numerous hay trucks that pass through Sentenac Canyon each day from the Imperial Valley and/or Colorado River hay fields.
Of course, it is also possible Calyptridium parryi var. arizonicum is native here, and simply not previously discovered here. For example, Jordan Zylstra was the first to recognize that the Sarcostemma cynanchoides at Pinyon Flat on the north side of the Santa Rosa Mountains was actually the only California population of the Arizona species Sarcostemma crispum. There is a known relationship between the plants along the east PR in California and plants at the eastern edge of the Sonoran Desert in Arizona (see below).
- This canyon has only the seventh known location of Carlowrightia arizonica in California, found by James Dillane, Tom Chester and Kate Harper on 12 December 2012. This species is only found in fairly small numbers at each of the seven locations.
Five of the seven populations, including this one, are in an area only 14 miles long and a few miles wide, all north of Plum Canyon except for the fairly nearby Mine Canyon population, with the other two populations disjunct by 9 miles and 20 miles to the south of this location. Only two of the seven populations made it into the 2012 Second Edition Jepson Manual Treatment, since most of the other five populations have only been recently discovered.
The last two highlights show that there is still much to be learned about the flora of California, with surprises waiting in many areas.
Both of these two species are disjuncts from Arizona, which shows that this area has some additional affinity to the flora of southwest Arizona other than the lower-elevation widespread species such as creosote and ocotillo. These disjunct species are separated from their Arizona siblings with a large area in-between currently without any of these species. The connection probably occurs during the cool phase of the Ice Ages, which lasts some 90% of one glacial cycle, when these species may expand their ranges so that the Arizona and California populations approach each other more closely. There have been roughly 24 such cycles, each lasting ~100,000 years, in the last 2.4 million years since the Ice Ages began.
Long-distance dispersal is also a possibility, but the number of other disjuncts, such as Arctostaphylos pringlei at higher elevations, makes a geographic connection of the range of these species during wetter, cooler times more likely.
Procedure For Compiling The Checklist
The Checklist was compiled from two sources:
- Fieldwork done on
- 12 December 2012 by Tom Chester, James Dillane and Kate Harper;
- 24 December 2010 by Kate Harper, adding two species (Senna covesii and Delphinium parishii ssp. subglobosum) from a mostly-hiking trip;
- 21 December 2012 by Tom Chester, James Dillane and Jim Roberts;
- 5 March 2011 by Keir Morse, adding four species from his photographs
- 27 March 2011 by Keir Morse in the canyon immediately east, adding six species as target species to the Plum Canyon list;
- 28 December 2012 by Tom Chester and Keir Morse, mostly in the canyon immediately east;
- 2 January 2013 by Tom Chester in the south branch of upper Plum Canyon; and
- 22 March 2013 by Tom Chester, Adrienne Ballwey and Kate Harper in the north branch of upper Plum Canyon, from the parking area to the saddle.
- Vouchers compiled from a search of the Consortium of California Herbaria on 11 December 2012 by Tom Chester.
The areas surveyed by the 12 and 21 December 2012 fieldwork are shown by the blue lines in the Google Earth View shown above.
The fieldwork on 21 December 2012 was primarily to find traces of the old Wagon Road, with only incidental botanizing.
The 12 December 2012 fieldwork was used to compile a species list, with a GPS location for at least one occurrence of every species, and to estimate abundances for each observed species. Note that the fieldwork list is extremely incomplete for annuals and perennials, since it was made from field trips at the worst-possible time of year, in late fall, which covered only a small area of the canyon along the main hiking route from SR78 to one of the several saddles at the top. We did not attempt to identify dead annuals except for those whose determinations were unambiguous from their remnants. The abundances for those dead annuals may be severely underestimated.
A species list was compiled from the 24 December 2010 fieldwork, but no GPS locations or abundances were recorded.
Species lists were not compiled from the other fieldwork. The 21 December 2012 and 2 January 2013 fieldwork noted any new species, and increased the abundances of a number of species. Notes and photographs from the other trips were used to add species to the plant list.
The 27 March 2011 and 28 December 2012 fieldwork was done primarily in the canyon directly east of Plum Canyon. Because the Plum Canyon List is incomplete for annuals and perennials, species seen only in that canyon were added to the Plum Canyon list as target species, ones to be looked for in Plum Canyon, and so identified in the checklist below.
The fieldwork found 111 distinct taxa in Plum Canyon, plus five additional taxa from the canyon to the east, for a total of 116 taxa.
Vouchers were obtained from three separate searches:
- using coordinates, for the rectangular box from 33.09 to 33.13° north latitude and -116.44 to -116.40° east longitude which included an area slightly larger than just Plum Canyon;
- vouchers with Plum Canyon in their localities; and
- vouchers with Wagon Wash in their localities.
Vouchers by Jepson were examined for "missing numbers", resulting in the addition of two vouchers.
Duplicate vouchers were removed, and the localities were reviewed manually to remove ones not in Plum Canyon. Six vouchers were badly georeferenced; 134 were clearly from outside Plum Canyon, with most in Sentenac Canyon or along SR78 outside the Plum Canyon area. 18 vouchers were from wash 300 yds W of Plum Canyon, which drains into the San Felipe River just upstream from Plum Canyon Wash, and hence were excluded.
Iti isn't clear whether the ten Jepson vouchers from 22 April 1928 were from the south fork of Plum Canyon, or from the entirely-separate canyon immediately east of Plum Canyon. Near SR78, the wash from the separate canyon is only 400 feet east of Plum Canyon Wash. He wrote:In the morning Apr. 22 we drove back to Wagon Wash and I walked up the wash and into Mule-track Canon, the large canon to left of Wagon Wash Canon, and collected cacti.
Yet more confusingly, most of his vouchers from that day give Wagon Wash as the locality, with only two of the ten vouchers giving Mule-track Canyon in its locality, one of which also said Wagon Wash.
We have included his vouchers in this Checklist for now, but may exclude them in the future if some of the vouchered species are not found by us in the field in Plum Canyon. In the checklist below, two species were vouchered only from this set: Castilleja foliolosa and Pleurocoronis pluriseta.
One voucher determination was not accepted, of Opuntia wolfii = Cylindropuntia wolfii, by Jepson in 1928, JEPS66889. This species lives only much farther south, and hence this is unlikely to be the correct determination. It is most likely this is a specimen of C. ganderi, which was not recognized until 1938.
One voucher simply determined as Agave, also collected by Jepson in 1928, JEPS43125, was taken to be A. deserti, which is the only Agave species present in the Borrego Desert.
A few taxa were combined, when some were given as the species and others as the subspecies, and it was clear that only a single taxon was present.
That left 232 vouchers, of 122 distinct taxa.
The top collectors in Plum Canyon are:
# Vouchers Collector(s) 78 Larry Hendrickson 72 W. L. Jepson 28 Jeannie Gregory, John Gregory 22 Jon P. Rebman, J. Gibson, A. Winner, & misc. botany vols. 10 Bill Sullivan
The union of the checklist from the fieldwork and the vouchers contains 175 taxa. Of those 175 taxa, 63 taxa were found in both the fieldwork and the vouchers; 59 were found only in the vouchers; 48 were found only from the fieldwork; and 5 taxa are listed as target species after being found in the canyon to the east.
Nearly all of the 59 species that were vouchered, but not seen in our fieldwork, were annuals or perennials that one would not expect to see in December. All of the 48 species seen in the fieldwork, and the 5 target species, that do not have vouchers in Plum Canyon have vouchers elsewhere in the Borrego Desert; most of those have vouchers from the immediate area surrounding Plum Canyon.
The Checklist follows the 2012 Jepson Manual Second Edition with only a few exceptions.
The Checklist is sorted first by the eight evolutionary categories (clades) used in the 2012 Second Edition Jepson Manual - lycophytes, ferns, etc., to eudicots and monocots - and then by family and scientific name. The clades are labeled in the Checklist. Note that this changes the order of presentation of the taxa from that of the 1993 First Edition.
The family name is abbreviated to the first six characters in order to save space in the table rows.
An asterisk before the Common Name indicates a non-native taxon.
The column labeled #Pls gives a minimum estimate of the number of plants from the field surveys, up to a maximum of 99 plants, for species seen in the field surveys for which abundances were noted. The main intent of this estimate is to indicate the species for which we found very few plants. If the species was added from Keir Morse's photographs from 5 March 2011, the column contains his initials, KM. If the species was seen only in the canyon immediately to the east, it is present in the list as a target species, one to be looked for in Plum Canyon, and the column contains TGT.
The column labeled #V gives the number of vouchers in Plum Canyon.
The scientific name is linked to the latest online Jepson Manual description for each species, which also gives the months in which each species flowers. That link also gives a map of where the species occurs in California; a plot of elevation vs. latitude for California; and a histogram of the voucher collections by month.
A few species may not have working links, if their names have been updated more recently (such as Mimulus diffusus, which is still listed under M. palmeri in the online flora), or if they are reserved-judgment taxa which are listed in the entry for another taxon name. However, as of 26 December 2012, the Jepson Manual links have all been updated to link to the parent species for the taxa without their own entries. Taxa linked to anything other than the Jepson Manual link for the full scientific name used below have been indicated with a ^ after the scientific name, and are discussed here.
The common name for most species in the checklist is linked to Calphotos to give pictures of most taxa. Of course, there is no guarantee that the Calphotos pictures are correctly identified.
Note that the link will not always return pictures, since not every species has pictures at Calphotos, and a number of species still have their Calphotos pictures under the Jepson Manual First Edition Names. Some links have been made to the Calphotos pictures using the First Edition Jepson Manual name, if there are no pictures under the Second Edition name. Of course, that may result in a link with no pictures if those the names of those Calphotos pix are updated in the future to the Second Edition names.
Note also that the links below will return only the specified taxon at Calphotos, and not any subtaxa; i.e., a link to Cryptantha barbigera will not return photos of Cryptantha barbigera var. barbigera. There may be additional pictures at Calphotos under a different scientific name such as the First Edition Jepson Manual name.
Some links, such as for Bochera perennans, go to special pages with more information on those species.
As of 26 December 2012, the picture links have all been updated to link to a page that has pictures. Taxa linked to anything other than the Calphotos page of their full scientific name used below have been indicated with a ^ after the common name.
If you find any links from either the scientific or common names below that do not work, please let us know so we can update them.
Version for printing, without lines and other text on this page: html (6 pages) or pdf Clickbook booklet (2 double-sided pages). (See printing instructions for an explanation of these options)
# Family Scientific Name (*) Common Name #V #Pls Lycopods 1 Selagi Selaginella bigelovii Bigelow's spike-moss 99 2 Selagi Selaginella eremophila desert spike-moss 99 Ferns 3 Pterid Cheilanthes covillei beady lipfern 2 13 4 Pterid Cheilanthes parryi woolly lipfern 5 99 5 Pterid Cheilanthes viscida sticky lipfern 1 6 Pterid Notholaena californica ssp. californica^ California cloak fern 1 7 Pterid Pellaea mucronata var. mucronata bird's-foot fern 1 Gymnosperms 8 Cupres Juniperus californica California juniper 1 99 9 Ephedr Ephedra aspera Mormon tea 2 99 10 Ephedr Ephedra californica desert tea 2 Eudicots 11 Acanth Carlowrightia arizonica Arizona carlowrightia 15 12 Acanth Justicia californica chuparosa 7 99 13 Amaran Amaranthus fimbriatus fringed amaranth 99 14 Apiace Apiastrum angustifolium wild celery 2 15 Apiace Lomatium mohavense Mojave lomatium 8 16 Apocyn Matelea parvifolia spearleaf 1 16 17 Astera Acamptopappus sphaerocephalus var. sphaerocephalus goldenhead 1 18 Astera Adenophyllum porophylloides San Felipe dogweed 2 99 19 Astera Ambrosia dumosa burroweed 1 99 20 Astera Ambrosia salsola var. salsola cheesebush^ 1 99 21 Astera Artemisia ludoviciana ssp. albula white mugwort 25 22 Astera Baccharis brachyphylla short-leaved baccharis 70 23 Astera Bahiopsis parishii Parish's viguiera 2 99 24 Astera Bebbia juncea var. aspera sweetbush 1 99 25 Astera Brickellia atractyloides var. arguta California spear-leaved brickellia 11 26 Astera Brickellia frutescens shrubby brickellia 1 40 27 Astera Chaenactis carphoclinia var. carphoclinia pebble pincushion 5 28 Astera Chaenactis fremontii Fremont pincushion 1 99 29 Astera Encelia farinosa brittlebush 1 99 30 Astera Ericameria brachylepis boundary goldenbush^ 99 31 Astera Ericameria paniculata blackbanded rabbitbrush 20 32 Astera Eriophyllum wallacei var. rubellum^ Wallace's woolly daisy^ 3 99 33 Astera Gutierrezia californica California matchweed 99 34 Astera Lasthenia gracilis goldfields 1 99 35 Astera Logfia depressa dwarf filago 1 36 Astera Logfia filaginoides California filago 99 37 Astera Malacothrix glabrata desert dandelion 2 99 38 Astera Monoptilon bellioides desert star 1 39 Astera Pectis papposa var. papposa chinch-weed 10 40 Astera Perityle emoryi Emory's rock-daisy 1 1 41 Astera Pleurocoronis pluriseta arrow-leaf 1 42 Astera Porophyllum gracile odora 2 40 43 Astera Rafinesquia neomexicana desert chicory 3 44 Astera Senecio californicus California groundsel 1 5 45 Astera Stephanomeria exigua ssp. exigua slender wreathplant 2 46 Astera Stephanomeria pauciflora wire-lettuce 25 47 Astera Trichoptilium incisum yellow-head 1 48 Astera Trixis californica var. californica California trixis 4 30 49 Bignon Chilopsis linearis ssp. arcuata desert-willow 4 50 Boragi Amsinckia intermedia common fiddleneck 1 25 51 Boragi Amsinckia tessellata var. tessellata bristly fiddleneck TGT 52 Boragi Cryptantha barbigera var. barbigera bearded cryptantha 3 5 53 Boragi Cryptantha decipiens gravel cryptantha 1 54 Boragi Cryptantha micrantha var. micrantha red-root cryptantha KM 55 Boragi Cryptantha muricata prickly cryptantha 1 56 Boragi Cryptantha pterocarya var. cycloptera Tucson wing-nut cryptantha 10 57 Boragi Emmenanthe penduliflora var. penduliflora whispering bells 2 20 58 Boragi Eucrypta chrysanthemifolia var. bipinnatifida eucrypta 1 8 59 Boragi Nama demissum var. demissum purple mat 2 15 60 Boragi Pectocarya platycarpa broad-fruited combseed KM 61 Boragi Pectocarya recurvata curvenut combseed 2 2 62 Boragi Pectocarya setosa moth combseed 1 63 Boragi Phacelia distans common phacelia 4 99 64 Boragi Phacelia minor wild canterbury bells 2 13 65 Boragi Phacelia pedicellata pedicellate phacelia 1 66 Boragi Pholistoma membranaceum white fiesta flower 4 99 67 Brassi Boechera perennans perennial rock-cress^ 22 68 Brassi Brassica tournefortii *Asian mustard 99 69 Brassi Caulanthus cooperi Cooper's jewel-flower 2 2 70 Brassi Caulanthus hallii Hall's caulanthus 7 71 Brassi Caulanthus lasiophyllus California mustard 2 2 72 Brassi Descurainia pinnata alkali western tansy-mustard 2 73 Brassi Lepidium lasiocarpum ssp. lasiocarpum hairy-podded pepper-grass^ 1 20 74 Brassi Lyrocarpa coulteri Coulter's lyrepod 1 75 Brassi Thysanocarpus curvipes fringe-pod 2 7 76 Brassi Tropidocarpum gracile slender tropidocarpum KM 77 Cactac Cylindropuntia bigelovii teddy-bear cholla 1 99 78 Cactac Cylindropuntia californica var. parkeri cane cholla 2 79 Cactac Cylindropuntia ganderi Gander's cholla 1 99 80 Cactac Echinocereus engelmannii Engelmann's hedgehog cactus 3 99 81 Cactac Ferocactus cylindraceus California barrel cactus 2 99 82 Cactac Mammillaria dioica California fish-hook cactus 1 12 83 Cactac Mammillaria tetrancistra fish-hook cactus 1 3 84 Cactac Opuntia basilaris var. basilaris beavertail cactus 2 80 85 Cactac Opuntia engelmannii var. engelmannii Engelmann prickly-pear 8 86 Cactac Opuntia phaeacantha desert prickly-pear 15 87 Campan Nemacladus glanduliferus glandular nemacladus 5 88 Campan Nemacladus rubescens desert nemacladus 2 1 89 Crassu Crassula connata pygmy-weed 1 90 Crassu Dudleya saxosa ssp. aloides desert dudleya 1 44 91 Euphor Bernardia incana western bernardia^ 12 92 Euphor Chamaesyce melanadenia red-gland spurge 40 93 Euphor Chamaesyce micromera Sonoran spurge 99 94 Euphor Chamaesyce polycarpa small-seeded spurge 2 99 95 Euphor Chamaesyce setiloba starfish (Yuma) spurge 2 25 96 Euphor Ditaxis lanceolata narrowleaf ditaxis 6 80 97 Euphor Ditaxis neomexicana New Mexico ditaxis 1 99 98 Euphor Euphorbia eriantha beetle spurge 1 99 99 Euphor Stillingia linearifolia linear-leaved stillingia 2 50 100 Fabace Acmispon glaber var. brevialatus short-winged deerweed^ 5 99 101 Fabace Acmispon maritimus var. brevivexillus short-bannered coastal lotus 1 102 Fabace Acmispon rigidus desert lotus 5 103 Fabace Acmispon strigosus strigose lotus 4 99 104 Fabace Astragalus palmeri Palmer's milk-vetch 1 1 105 Fabace Dalea mollissima downy dalea 2 106 Fabace Lupinus arizonicus Arizona lupine 1 107 Fabace Lupinus concinnus bajada lupine 40 108 Fabace Lupinus sparsiflorus Coulter's lupine 3 109 Fabace Marina parryi Parry's marina 7 99 110 Fabace Prosopis glandulosa var. torreyana honey mesquite 1 1 111 Fabace Psorothamnus schottii indigo bush 3 99 112 Fabace Psorothamnus spinosus smoke tree 10 113 Fabace Senegalia greggii catclaw 99 114 Fabace Senna covesii Coves's cassia 2 36 115 Fouqui Fouquieria splendens ssp. splendens ocotillo 99 116 Gerani Erodium cicutarium *redstem filaree 1 99 117 Gerani Erodium texanum Texas filaree 2 118 Kramer Krameria bicolor white rhatany 99 119 Kramer Krameria erecta Pima rhatany 1 120 Lamiac Hyptis emoryi desert-lavender 3 99 121 Lamiac Salvia apiana white sage 3 99 122 Lamiac Salvia columbariae chia 1 99 123 Loasac Mentzelia albicaulis white-stemmed blazing star 3 124 Loasac Mentzelia veatchiana Veatch's blazing star 1 125 Loasac Petalonyx thurberi ssp. thurberi Thurber's sandpaper-plant 1 126 Malvac Ayenia compacta ayenia 1 15 127 Malvac Hibiscus denudatus rock hibiscus 3 128 Malvac Sphaeralcea ambigua var. ambigua apricot mallow 2 20 129 Mollug Mollugo cerviana *carpet-weed 35 130 Montia Calyptridium monandrum sand cress 1 30 131 Montia Calyptridium parryi var. arizonicum Arizona sand cress^ 2 132 Nyctag Allionia incarnata trailing four o'clock 5 133 Nyctag Boerhavia coulteri var. palmeri Coulter's spiderling 99 134 Nyctag Boerhavia triquetra var. intermedia fivewing spiderling 99 135 Nyctag Mirabilis laevis var. retrorsa Bigelow's desert four-o'clock 2 50 136 Nyctag Mirabilis laevis var. villosa Bigelow's desert four-o'clock 1 137 Oleace Menodora scabra var. glabrescens broom twinberry 1 138 Onagra Camissoniopsis ignota Jurupa Hills sun-cups^ 1 2 139 Onagra Camissoniopsis pallida ssp. pallida pale sun-cup 50 140 Onagra Chylismia claviformis ssp. peirsonii brown-eyed primrose 2 1 141 Onagra Eulobus californicus California suncup 1 99 142 Oroban Castilleja foliolosa woolly Indian paintbrush 1 143 Papave Eschscholzia minutiflora ssp. minutiflora^ small-flowered poppy 4 99 144 Papave Eschscholzia parishii Parish's poppy 2 145 Phryma Mimulus bigelovii var. bigelovii Bigelow's monkeyflower 2 30 146 Planta Antirrhinum filipes desert twining snapdragon 1 147 Planta Mohavea confertiflora ghost flower 1 148 Polemo Eriastrum eremicum ssp. eremicum desert woolly-star 3 99 149 Polemo Gilia stellata star gilia 1 13 150 Polemo Langloisia setosissima ssp. setosissima bristly langloisia TGT 151 Polemo Loeseliastrum schottii Schott's calico TGT 152 Polygo Centrostegia thurberi red triangles 1 153 Polygo Chorizanthe brevicornu var. brevicornu brittle spineflower 1 1 154 Polygo Chorizanthe fimbriata var. laciniata lace-fringed spineflower 2 155 Polygo Eriogonum davidsonii Davidson's buckwheat 5 156 Polygo Eriogonum fasciculatum var. polifolium California buckwheat 1 99 157 Polygo Eriogonum inflatum desert trumpet 2 50 158 Polygo Eriogonum plumatella yucca buckwheat 3 159 Polygo Eriogonum thomasii Thomas' buckwheat 1 160 Polygo Eriogonum wrightii var. nodosum Wright's buckwheat 2 99 161 Polygo Pterostegia drymarioides threadstem 2 162 Ranunc Delphinium parishii ssp. subglobosum intermediate larkspur 20 163 Rhamna Ziziphus parryi var. parryi lotebush 1 5 164 Rosace Coleogyne ramosissima black brush 1 99 165 Rosace Prunus fremontii desert apricot 7 99 166 Rubiac Galium stellatum star-flowered bedstraw 4 99 167 Rutace Thamnosma montana turpentine broom 3 42 168 Simmon Simmondsia chinensis jojoba 1 90 169 Solana Lycium andersonii Anderson's desert-thorn 1 50 170 Solana Lycium cooperi Cooper's box-thorn 1 5 171 Solana Nicotiana obtusifolia desert tobacco 7 172 Solana Physalis crassifolia thick-leaved ground cherry 2 50 173 Urtica Parietaria hespera var. hespera pellitory 1 40 174 Viscac Phoradendron californicum desert mistletoe 1 40 175 Zygoph Larrea tridentata creosote bush 2 99 Monocots 176 Agavac Agave deserti var. deserti desert agave 1 99 177 Agavac Yucca schidigera Mohave yucca 1 99 178 Alliac Allium fimbriatum var. fimbriatum fringed onion 1 179 Poacea Aristida adscensionis six-weeks three-awn 1 180 Poacea Aristida purpurea purple three-awn 40 181 Poacea Bouteloua aristidoides var. aristidoides needle grama 1 182 Poacea Bromus madritensis ssp. rubens *red brome 99 183 Poacea Dasyochloa pulchella fluff grass 1 184 Poacea Hilaria rigida big galleta 18 185 Poacea Melica frutescens tall melica 3 25 186 Poacea Muhlenbergia microsperma littleseed muhly 11 187 Poacea Poa secunda ssp. secunda one-sided bluegrass 20 188 Poacea Schismus barbatus *Mediterranean schismus 99 189 Poacea Stipa parishii var. parishii Parish's needlegrass^ 20 190 Poacea Stipa speciosa desert needlegrass 2 30 191 Themid Muilla maritima muilla 3
Voucher data provided by the participants of the Consortium of California Herbaria (ucjeps.berkeley.edu/consortium/).
We thank Jim Roberts for his help with the survey on 21 December 2012, and Keir Morse for the additions from his photographs, and for his help with the part of the 28 December 2012 survey in Plum Canyon.
Copyright © 2012-2013 by Larry Hendrickson, Tom Chester, James Dillane, Kate Harper and Adrienne Ballwey
Permission is freely granted to reproduce any or all of this page as long as credit is given to us at this source:
Comments and feedback: Tom Chester
Updated 25 March 2013.