Plant Species of the Borrego Desert: The Nifty Fifty: The 51 Most Common Species
Table of Contents
Analysis of the List
Sort by Abundance
Sort by Family
The page gives the most common 51 species of the Borrego Desert. Those top 51 species are defined as those occurring in nine or more of the 24 individual surveys I've done as of 29 December 2008. (OK, one more than 50, but Nifty Fifty sounds better than Nifty Fifty-one, and matches the name of the popular common stocks of the 1960s and 1970s. Artistic license, you know.)
Caution: this list is preliminary, and should not be used for scientific purposes until I've finished my flora of the Borrego Desert. In particular, the results may change in the future as more fieldwork is done and more of my previous fieldwork is digitized, especially as more survey locations are added and more fieldwork is done when annuals are present.
To help understand what this list represents, it may help to understand examples of what this list does not represent:
- This is not a list of the most common plants in any one specific area or habitat. For that purpose, consult the Floras and Plant Trail Guides for specific areas.
- This is not a list of the most common plants seen in the peak flowering season, or at any other particular time of year.
- This is not a list of the most abundant plants throughout the entire surveyed area.
- This is not a list of my personal favorite species.
For example, this list does not contain many of the common species found in the sandy habitat along Henderson Canyon and Di Giorgio Roads such as hairy sand verbena, Abronia villosa var. villosa; desert dicoria, Dicoria canescens; and hairy desert-sunflower, Geraea canescens. Those species have been found, respectively, in only 2, 5, and 2 of my 24 surveyed areas so far. Although those species are both common and widespread because their habitat is common and widespread along the desert floor, their habitat is not found in most of my surveyed areas, and thus these species don't make the list here.
This example of plants confined to a specific habitat gives insight into what the list presented here actually represents. Most species are like the three species mentioned above, confined to a single habitat. Examples of habitats and species confined to that habitat, along with the number of survey areas in which each named species was found, are given in the following table:
Habitat Species confined to that Habitat #
Common Name Scientific Name Gravelly washes subject to flooding that scarifies seeds smoke tree Psorothamnus spinosus 13 Moderately saline areas four-wing saltbush Atriplex canescens 8 Steep canyon walls of solid rock arrow-leaf Pleurocoronis pluriseta 6 Seeps, springs, streamsides California fan palm Washingtonia filifera 3 Rocky slopes among boulders pygmy-cedar Peucephyllum schottii 3 Sandy places hairy sand verbena Abronia villosa var. villosa 2 Extremely saline areas iodine-bush Allenrolfea occidentalis 2 Permanent streams Fremont cottonwood Populus fremontii 2
Of the species in the above table, only smoke tree, Psorothamnus spinosus, exceeds the cutoff of 9 or more survey areas and is present in the top 51 list here. Even though it is confined to a very specific habitat, that habitat is widespread through my surveyed areas. Four-wing saltbush, Atriplex canescens, just misses the cut-off. Its habitat of moderately saline areas is fairly widespread, but not quite enough to make the cutoff here.
In addition, many species are confined to geographic habitats with specific sets of conditions. Some of these habitats can be easily understood by mere mortals, such as the species that are confined to the Desert Transition Zone near the east base of the Peninsular Range where they find the only combination of heat, rainfall and cold that they can thrive in. Examples are desert apricot, Prunus fremontii; and lotebush, Ziziphus parryi, each found in two surveyed areas. Other species seem to be confined to specific habitats that are hard for humans to comprehend.
To see what the list does represent, here are the habitats of the two species found in all 24 surveyed areas. Burroweed, Ambrosia dumosa, is said to grow in Creosote Bush Scrub, meaning it grows essentially everywhere that the other top species, creosote, Larrea tridentata, grows. Creosote gives its name to its plant community, since it grows almost everywhere in the Sonoran desert, thriving in or at least tolerating a large number of habitats, under many different geographic conditions.
Those two species are not picky about where they grow, and are among the small number of species that successfully grow in many different conditions. In fact, Forrest Shreve, in Vegetation and Flora of the Sonoran Desert, says that these two species vastly outnumber all others in the Lower Colorado Valley subdivision, which includes the Borrego Desert (p. 49). The primary reason for this dominance is that these are the last two shrub species to drop out as the rainfall diminishes.
Note that such widespread common species are rare; see the histogram below that demonstrates the well-known biological law that common species are few in number; rare species are common in number.
Many of the other species on the list are similar non-picky species, but many others occur in specific habitats that are found in nearly every surveyed area, such as smoke tree. Other examples are cheesebush, Ambrosia salsola var. salsola; and desert-lavender, Condea emoryi, which grow in any wash that has enough seasonal moisture for them.
- Annuals and perennials are often wildly underestimated in many of these surveys, since about half of the surveys were done outside the narrow window in which many such species can be found and confidently identified. Thus the survey can be considered complete only for shrubs, cacti, trees, and those annuals or perennials that can be confidently identified from dead plant remnants.
Cryptantha species may suffer most from underestimation since one needs live plants with mature fruit to confidently identify them. Probably due to the short window for confident identification, no Cryptantha species made the list. The most abundant species, C. barbigera, just missed the cutoff, being seen so far in 8 of these surveys. It is highly likely that C. barbigera and C. angustifolia will be present on the list after all 24 surveys have been surveyed in prime time.
However, since about ten of the surveys were done in prime time, very widespread annuals and perennials had at least some chance to make this list. In fact, half the list consists of annuals and perennials.
- Note that my definition of the Borrego Desert above is the portion in the 24 individual surveys carried out so far. This is a pretty restrictive definition; see the map below showing the surveyed areas. There are large areas of the Borrego Desert not yet surveyed, and the current list given here may change as more areas are sampled.
- Note that the definition of Common used above means that these species are simply widespread among my survey locations, and not necessarily abundant. It only takes a single individual to be counted in a survey, so rare but widespread species will appear in this list alongside very abundant and widespread species.
However, in fact, nearly all of these species are also quite abundant. A future version of this list will include the abundances from each survey.
The following map of the Borrego Desert shows where the surveys have been conducted so far:
Each dot roughly corresponds to the midpoint of each survey. Most of these surveys are detailed in preliminary Floras and Plant Trail Guides.
Each survey typically covered a linear distance of four miles or so, sometimes along a single trail and sometimes along a loop. The elevations surveyed ranged from 200 feet in the extreme northeast corner of the county, to 2600 feet in Hellhole Canyon. The mean elevation of the surveys was 1000 feet, with most of the area surveyed between 500 and 1500 feet. Note that the map above shows the 1000 foot and 3000 foot elevation contours.
This page can be used by beginning students of the Borrego Desert flora as a list of species to learn first, as well as by photographers trying to learn the species name for a common flower they photographed without having to wade through the 373 species I've observed so far, or the 641 species including records from others from this entire area. People familiar with the Borrego Desert can check to see if they know all of the top 51 species.
For those itching to know the next most common species, see The 172 Most Common Species, which includes the top 51 species.
Analysis of the List
The following histogram gives the number of surveys in which each taxon was found:
This histogram follows the usual shape, in which only a very few species are ubiquitous, with most species being found in only one or two surveys. Hence the statement above that common species are few in number; rare species are common in number. For more information on how this histogram was derived, and why this is the usual shape, see How Common Are The Plants Of Southern California? and Plants of Southern California: Introduction and Explanation of Trail Guides. The plotted curve through the data points is a fairly good fit, indicating that survey incompleteness is not a significant factor overall.
The following histogram gives the number of species in this list by plant habit, sorted first alphabetically by habit and then sorted by abundance:
Sort Alphabetically By Habit Sort Numerically By Abundance Habit H # % Habit H # % Annual A 18 35% Annual A 18 35% Cactus C 6 12% Shrub / Subshrub S 17 33% Fern F 1 2% Perennial P 8 16% Perennial P 8 16% Cactus C 6 12% Shrub / Subshrub S 17 33% Fern F 1 2% Tree T 1 2% Tree T 1 2%
The column H gives the abbreviation used for the plant habit in the checklists below.
The Nifty Fifty are presented in two ways below. In both versions, the Family and Scientific Name are from the Jepson eflora as of 10 January, 2023. An asterisk before the Common Name indicates a non-native taxon. #S is the number of surveys in which each taxon was found. H is the abbreviation used for the plant habit, given in the table above.
First, the checklist is presented in descending order of abundance, sorted by the number of surveys in which each taxon was found. Second, it is presented in traditional family order: sorted first by category - ferns, eudicots, and monocots - and then by family and scientific name.
The checklist contains Krameria grayi, but not its sister species of Krameria erecta. These two species are very difficult to tell apart without fruit, which is not always present, and thus readers may wonder how common K. erecta is. K. erecta appears in 8 lists, and thus just missed the cutoff of 9, compared to the 18 lists that contained K. grayi.
In the following two checklists, the Scientific Names have been updated by Don Rideout from the 1993 Jepson Manual system to the names used the Jepson eflora as of 10 January 2023.
The Checklist Sorted by Abundance
# #S H JM Family Scientific Name (*)Common Name 1 24 S Asteraceae Ambrosia dumosa burroweed 2 24 S Zygophyllaceae Larrea tridentata creosote bush 3 23 S Fabaceae Psorothamnus schottii indigo bush 4 22 S Asteraceae Encelia farinosa brittlebush 5 22 P Euphorbiaceae Euphorbia polycarpa small-seeded spurge 6 22 S Fouquieriaceae Fouquieria splendens ssp. splendens ocotillo 7 21 S Asteraceae Ambrosia salsola var. salsola cheesebush 8 21 A Brassicaceae Brassica tournefortii *Asian mustard 9 21 A Onagraceae Eulobus californicus California suncup 10 21 P Poaceae Hilaria rigida big galleta 11 19 S Asteraceae Bebbia juncea var. aspera sweetbush 12 19 P Asteraceae Stephanomeria pauciflora var. pauciflora wire-lettuce 13 19 S Fabaceae Senegalia greggii catclaw 14 19 S Lamiaceae Condea emoryi desert-lavender 15 18 S Krameriaceae Krameria bicolor white rhatany 16 17 C Cactaceae Cylindropuntia ganderi Gander's cholla 17 17 C Cactaceae Opuntia basilaris var. basilaris beavertail cactus 18 17 A Plantaginaceae Plantago ovata desert plantain 19 17 P Polygonaceae Eriogonum inflatum desert trumpet 20 16 C Cactaceae Ferocactus cylindraceus California barrel cactus 21 15 A Asteraceae Perityle emoryi Emory's rock-daisy 22 14 A Onagraceae Eremothera boothii ssp. condensata Booth's evening primrose 23 14 A Polygonaceae Chorizanthe brevicornu var. brevicornu brittle spineflower 24 14 P Viscaceae Phoradendron californicum desert mistletoe 25 13 T Fabaceae Psorothamnus spinosus smoke tree 26 13 A Onagraceae Chylismia claviformis ssp. peirsonii brown-eyed primrose 27 13 A Poaceae Schismus barbatus *Mediterranean schismus 28 12 A Brassicaceae Lepidium lasiocarpum var. lasiocarpum hairy-podded pepper-grass 29 12 C Cactaceae Cylindropuntia echinocarpa silver cholla 30 12 A Hydrophyllaceae Phacelia distans common phacelia 31 12 S Zygophyllaceae Fagonia laevis California fagonia 32 11 A Asteraceae Rafinesquia neomexicana desert chicory 33 11 C Cactaceae Cylindropuntia bigelovii teddy-bear cholla 34 11 P Euphorbiaceae Ditaxis lanceolata narrowleaf ditaxis 35 11 A Fabaceae Lupinus arizonicus Arizona lupine 36 11 A Hydrophyllaceae Phacelia crenulata var. ambigua heliotrope phacelia 37 11 A Loasaceae Mentzelia involucrata bracted blazing star 38 11 S Loasaceae Petalonyx thurberi ssp. thurberi Thurber's sandpaper-plant 39 11 P Malvaceae Hibiscus denudatus rock hibiscus 40 11 P Nyctaginaceae Mirabilis laevis var. retrorsa wishbone plant 41 10 C Cactaceae Cylindropuntia ramosissima pencil cholla 42 10 A Fabaceae Lupinus concinnus bajada lupine 43 10 S Fabaceae Psorothamnus emoryi Emory's indigo-bush 44 10 A Geraniaceae Erodium cicutarium *redstem filaree 45 10 A Lamiaceae Salvia columbariae chia 46 9 A Asteraceae Senecio mohavensis Mojave ragwort 47 9 S Asteraceae Trixis californica var. californica California trixis 48 9 S Boraginaceae Tiquilia palmeri Palmer's coldenia 49 9 S Chenopodiaceae Atriplex hymenelytra desert holly 50 9 S Chenopodiaceae Atriplex polycarpa cattle saltbush 51 9 F Pteridaceae Myriopteris parryi woolly lipfern
The Checklist Sorted by Family
# #S H JM Family Updated Scientific Name (*)Common Name 1 9 F Pteridaceae Myriopteris parryi woolly lipfern 2 24 S Asteraceae Ambrosia dumosa burroweed 3 21 S Asteraceae Ambrosia salsola var. salsola cheesebush 4 19 S Asteraceae Bebbia juncea var. aspera sweetbush 5 22 S Asteraceae Encelia farinosa brittlebush 6 15 A Asteraceae Perityle emoryi Emory's rock-daisy 7 11 A Asteraceae Rafinesquia neomexicana desert chicory 8 9 A Asteraceae Senecio mohavensis Mojave ragwort 9 19 P Asteraceae Stephanomeria pauciflora var. pauciflora wire-lettuce 10 9 S Asteraceae Trixis californica var. californica California trixis 11 9 S Boraginaceae Tiquilia palmeri Palmer's coldenia 12 21 A Brassicaceae Brassica tournefortii *Asian mustard 13 12 A Brassicaceae Lepidium lasiocarpum var. lasiocarpum hairy-podded pepper-grass 14 11 C Cactaceae Cylindropuntia bigelovii teddy-bear cholla 15 12 C Cactaceae Cylindropuntia echinocarpa silver cholla 16 17 C Cactaceae Cylindropuntia ganderi Gander's cholla 17 10 C Cactaceae Cylindropuntia ramosissima pencil cholla 18 16 C Cactaceae Ferocactus cylindraceus California barrel cactus 19 17 C Cactaceae Opuntia basilaris var. basilaris beavertail cactus 20 9 S Chenopodiaceae Atriplex hymenelytra desert holly 21 9 S Chenopodiaceae Atriplex polycarpa cattle saltbush 22 11 P Euphorbiaceae Ditaxis lanceolata narrowleaf ditaxis 23 22 P Euphorbiaceae Euphorbia polycarpa small-seeded spurge 24 11 A Fabaceae Lupinus arizonicus Arizona lupine 25 10 A Fabaceae Lupinus concinnus bajada lupine 26 10 S Fabaceae Psorothamnus emoryi Emory's indigo-bush 27 23 S Fabaceae Psorothamnus schottii indigo bush 28 13 T Fabaceae Psorothamnus spinosus smoke tree 29 19 S Fabaceae Senegalia greggii catclaw 30 22 S Fouquieriaceae Fouquieria splendens ssp. splendens ocotillo 31 10 A Geraniaceae Erodium cicutarium *redstem filaree 32 11 A Hydrophyllaceae Phacelia crenulata var. ambigua heliotrope phacelia 33 12 A Hydrophyllaceae Phacelia distans common phacelia 34 18 S Krameriaceae Krameria bicolor white rhatany 35 19 S Lamiaceae Condea emoryi desert-lavender 36 10 A Lamiaceae Salvia columbariae chia 37 11 A Loasaceae Mentzelia involucrata bracted blazing star 38 11 S Loasaceae Petalonyx thurberi ssp. thurberi Thurber's sandpaper-plant 39 11 P Malvaceae Hibiscus denudatus rock hibiscus 40 11 P Nyctaginaceae Mirabilis laevis var. retrorsa wishbone plant 41 13 A Onagraceae Chylismia claviformis ssp. peirsonii brown-eyed primrose 42 14 A Onagraceae Eremothera boothii ssp. condensata Booth's evening primrose 43 21 A Onagraceae Eulobus californicus California suncup 44 17 A Plantaginaceae Plantago ovata desert plantain 45 14 A Polygonaceae Chorizanthe brevicornu var. brevicornu brittle spineflower 46 17 P Polygonaceae Eriogonum inflatum desert trumpet 47 14 P Viscaceae Phoradendron californicum desert mistletoe 48 12 S Zygophyllaceae Fagonia laevis California fagonia 49 24 S Zygophyllaceae Larrea tridentata creosote bush 50 21 P Poaceae Hilaria rigida big galleta 51 13 A Poaceae Schismus barbatus *Mediterranean schismus
I thank Bill Sullivan for discussions which stimulated the extensive discussion in the Introduction about what this list does and does not represent. I thank Don Rideout for updating the scientific names in the two checklists.
Copyright © 2009 by Tom Chester. Scientific Names updated in the last two checklists on 10 January 2023 by Don Rideout
Commercial rights reserved. Permission is granted to reproduce any or all of this page for individual or non-profit institutional internal use as long as credit is given to me at this source:
Comments and feedback: Tom Chester
Last update: 10 January 2023