One of the methods used by researchers to validate the possible native presence of certain plants
is to compare plant communities of the subject plant with other known communities which
support similar biota.
Brown, Carmony, Lowe and Turner in their definitive article (Arizona Academy of Science
Vol. 11 Number 1 Feb. 1976) "A Second Locality for Native W. filifera In Arizona determined
that populations of Washingtonia filifera at or around Castle Creek Springs in Yavapai county in
Arizona were indeed "native" in part by comparisons of the area's riparian and typically riparian
communities to those listed by Vogl and McHargue in 1966 in their vegetative descriptions of
Palm Oases along the San Andreas Fault.
This is very important to do in the case of the Moapa region because there still appears to exist a
great deal of intellectual bias that the area around Moapa is somehow climatically or
environmentally different from the areas where Palms are anciently extant to the south.(1)
To conclusively show that not only is this not the case but rather that the area is in fact even
more like the Palm communities of California than are the plant communities around Castle
Creek and KOFA (where Palms are considered Native) I will first list the Plants which are
listed by Vogl and McHargue. Following this, I will show which of those plants are represented
at Castle Creek and which of those plants are represented in the area around Moapa for a
comparison.
The following plants are listed by Vogl and McHargue as riparian or typically riparian taxa
found in the vicinities of Palm Groves along the San Andreas Fault in California.
Acacia greggii
Ambrosia ambrososioides
Atriplex canescens
Baccharis glutinosa, sarothroides
Carex ultra
Celtis pallida
Cercidium floridum
Condalia lycioides
Cynodon dactylon
Haplopappus acradenius
Hymenoclea monogyra
Nicotiana palmeri
Penstemon subulatus
Phragmites communis
Pluchea sericea
Prosopis juliflora, glandulosa, pubescens
and:
Washingtonia filifera
Out of this list of 17 genera and 20 species, Castle Creek's "NATIVE PALM GROVES"exhibit
only eight genera and only six of the specific species listed.
Genera are listed with no "species" afterward if only the genus is found:
Acacia greggii
Atriplex ( )
Haplopappus acradenius
Hymenoclea ( )
Phragmites communis
Pluchea sericea
Prosopis juliflora
Washingtonia filifera
Compare this to the following list of Plants found within the ranges of Moapa Valley's Palms:
(Genera found in the vicinity of Palm groves in southern Nevada include the following genera.
Species which are not listed by Vogl & McHargue but found in Moapa are in Parentheses:)
Acacia greggii
Ambrosia (eriocentra)
Atriplex canescens
Baccharis blutinosa
Carex (occidentalis, subfuscia )
Celtis (reticulata)
Cynodon dactylon
Haplopappus acradenius
Hymenoclea (salsola)
Nicotiana (glauca, attenulata, triginofila*)(2)
Phragmites communis
Pluchea sericea
Prosopis glandulosa, pubescens & juliflora- (the last by Bradley & Deacon 1965:26-28)
Washingtonia filifera
As you can see, 14 out of 17 genera are found in the Lake Mead Region.(3)
As far as species go, the area exhibits at least 11 of those which are listed by Vogl and
McHargue. This is a greater percentage by far than that given by the research of Brown,
Carmony, Lowe and Turner for areas with provably Native Palms in Arizona's Castle Creek.
The above discussion amply establishes that as far as comparisons of riparian or typically
riparian plants associated with Palms in Southern Nevada are concerned, the possibility that
these Palms are indigenous to the region can neither reasonably nor effectively be discounted
due to any paucity of common or shared flora when compared to other provably indigenous
Palm communities. (Otherwise if Washingtonia filifera is shown to be indigenous to Southern
Nevada, which it surely must be, then it could equally be said that communities to the south are
deficient of certain taxa such as: Gutierrizia spp. Hymenoclea salsola, Salazoria mexicana and
Chilopsis linearis all of which occur near Moapa but apparently not in Palm Springs as of Vogl
and McHargue's writings.) I am certain this list could be expanded. However, there seems
little point in doing so.
Clearly then, no notion is implied here that all biota found in context with a specific plant are
necessarily obligate to all the communities of the subject plant at all locations. Such an idea
would seem unreasonable. Comparisons are simply tools for observation. Certainly one could
never infer that occurrences of specific plants are unlikely in certain regions simply due to
otherwise explainable paucity of often related taxa extant at the compared loci. If other
favorable factors are present and the subject plant is not clearly out of its possible indigenous
range, then barring any evidence to the contrary, it should be regarded with the native flora until
more conclusively shown otherwise.
Continuing the Plant comparisons however, I will now compare other plants (which occur in the
Moapa Region) to plants specifically used by Cahuilla of the Native Palm Groves there. A
favorable comparison or high degree of recurring instances of typically Ethnographically related
flora in such a context could serve the following;
a) to show climate variables for the specific plants are equally favored for such biota in both
regions,
b) to show reasonable cause exists for the subject plant to occur in the specified region.
c) to underscore Ethnobotanical similarities which may have existed between groups of Palm
using Aborigines.
To begin this discussion, I will turn our attention to the exhibits of the Palm Springs Desert
Museum. Listed here are a number of plants which were apparently all used by the Native
Americans of that region. Although I have not inquired into whether most of these plants were
used historically or otherwise by the Moapa Paiute, I have proceeded here in the following
fashion: If the plant is shown to exist in the Moapa region it is very likely the Moapa did use it
and they very well may have used it in similar ways. A "yes" next to the listed taxa signifies
that this particular plant is also found in the Lake Mead Region of Southern Nevada. A
species name in parentheses, (as before), indicates that this is the particular species of this plant
known to the Lake Mead Region. This is used only if there is sufficient similarity between
different species to facilitate shared or similar cross-cultural uses of a plant. When possible a
traditional use of the plant and ethnic group is noted. The notation of an ethnic group does in no
way preclude the likelihood that the plant was used by groups where ever it was found, only that
this plant has specifically been known to be used in the way mentioned by that particular ethnic
group.
Taxa exhibited at Palm Springs Museum Is the Taxa found in vicinity of Moapa?
Dalea (fremontii) -indigo bush Yes
Chupa Rosa or Beloperone Californica No
Salvia Columbariae -chia Yes used for food
Encelia farinosa -brittle brush Yes (Seri) used sap for glue
Geraea Canescens -desert sunflower Yes
Eriogum inflatum -desert trumpet Yes(4) used as greens, seed for flour, herb
Jimson datura -jimson weed Yes ritual hallucinogen
Isomeris arborea - bladderpod No
Salvia apiana No, (mojavensis) Yes (Cahuilla) ate seeds
Jojoba No
Yucca Yes used for food, soap, fiber, liquor
Mormon tea Yes tea, medicinal, other
Creosote bush Yes medicinal, rituals
Juncas Yes baskets Cahuilla, Moapa
Sumac Yes baskets Cahuilla, Moapa
Coyote melon Yes
Mesquite Yes flour cake, drinks, dessert
Pinyon Yes flour, etc
Castilleja chromosa -Indian paintbrush Yes nectar from flowers
Palafoxia Linearis -Spanish needle No
Calochortus kennedyi -Mariposa lily Yes bulbs roasted
Escholtzia parishi No (glyptosperma & minutiflora)Yes pollen facial cosmetic, herbal, greens
Nicotiana trigonophylla -desert tobacco Yes smoked
Camissonia claviformis -browneyed primrose Yes Tohono O'otam & Cahuilla ate leaves also
the white lined sphinx moth found with plant eaten
Pluchea sericea -arroweed Yes used with palms for huts, arrows
Mistletoe Yes medicinal, other
Ironwood tree No
Washingtonia filifera -Desert Fan Palm, Yes -Moapa, Cahuilla, Tohono O'otam & Pima
used for food, baskets, shelter, fire tools, etc. All these groups are part of the Uto Aztecan
or Shoshone based linguistic family and cultures.
Conclusions regarding Plant communities:
The foregoing discussion argues conclusively that the riparian communities extant with the
wild Washingtonia filifera groves in the Moapa region follow an unmistakably acceptable
pattern echoed in all the native groves throughout the plant's indigenous range. The remaining
plant comparisons offered by the Palm Springs Desert Museum's exhibits reiterate and
strengthen this argument enormously. Twenty three out of Twenty Eight plants listed by the
Palm Springs Desert Museum as having been important to the Native Americans of that
immediate area are found near the groves and within the traditional lands of the Moapa
Paiute of Southern Nevada. This is a profound and unmistakably important observation!!!
I believe it would be an understatement to say that the Moapa's food and medicinal resources
were clearly almost identical to those of the Cahuilla. There is the possible exception of
acorns which is not even mentioned here since that important Cahuilla food came from an
entirely different biotic community than found in the Palm Springs area. Oaks were furthermore
not within range of the Moapa to my knowledge ...although I could be mistaken about this.
In conclusion it is clear that the most important plant communities which made up the
environment of the Cahuilla also made up the environment of the Moapa.
With this in mind it almost seems redundant to write a section regarding climate. The former
notions of those who classed this area of Nevada with higher elevations and other climate zones
need to be revised. It is beyond the scope of this effort to attempt to convince certain people of
the obvious. Perhaps those who still doubt should become more well acquainted with the
tolerances of this particular palm tree. For not only is the Moapa area well within the tolerances
of this plant in regard to climate the plant additionally thrives in areas quite a bit higher in
elevation and somewhat colder in winter. Most of the remaining Mojave desert including
Twenty nine Palms in California are colder and higher than the Moapa region yet Twenty nine
palms is the location for a native grove of Palms which figures in local Aboriginal legend.
However just to reiterate these points I include this section of climate information for those
interested in scrutinizing this more closely.
Climate in Southern Nevada's Moapa region.
(for once Las Vegas is not included)
As a rule, Overton winter temperatures are from 2 to 8 degrees warmer (Fahrenheit) than Las
Vegas on a given day. Furthermore, although it may seem odd Logandale(5) (only a few miles
from Overton) happens to be in a micro- climatic "cold sink." Unfortunately, temperature data
has been collected there for many years even though my research and other climate data shows
that it misrepresents the entire area by as much as 12 degrees Fahrenheit. According to
observations of freeze data for the Lake Mead area (spanning more than ten years) Logandale
experienced an average of three times the number of days below freezing as did Moapa,
Overton, Rogers Springs and Stuart's Point. On summer evenings this marked cold sink effect
is clearly obvious even to the casual observer, by simply driving through Logandale with the car
windows down. (See Table 2)
Comparisons of average frost free days in Moapa area of NV to areas in Sonoran deserts:
Table 2- 'Locale' Comparisons of Average frost free days per year over a ten-year
period from 1972-1982 (in descending order)
Yuma 350 days
Overton 349 days
Logandale 310 days
(Below is a twenty-year average for the listed Sonoran communities for an interesting
comparison)
Phoenix 302 days
Tucson 242 days
Table 2-A Average minimum temperatures for the same areas
NOTE: all temps are given in Fahrenheit following the standard method used in collecting the
data.
Logandale 25.6 F
Overton 32.3 F
Yuma 36. F
NOTES ON TABLE 2- and 2 A
While the average number of frost-free days during the indicated period in Overton is
comparable to Yuma AZ for the same time period, the Average minimum temperature is
lowerby about 4 degrees. This suggests that while sub-freezing temps are equally as
infrequent in Overton as in Yuma they tend to be lower.(6) (Also longer in duration.)
Also once again Logandale is a great exception and consistently shows far lower freezing
temperatures than any of the surrounding areas. Just for example a comparison of the three
coldest days for the ten-year period referenced in the table:
Jan 1973 Logandale's lowest low was 17 deg F
Jan 1974 Logandale's lowest low was 15 deg F and in
Jan 1979 Logandale's lowest low was 15 deg F
For the exact SAME periods 11 miles away for Overton
Jan 1973 Overton's lowest low was 25 deg F (a full 8 degrees higher)
Jan 1974 Overton's lowest low was 22 deg F (a full 7 degrees higher) and in
Jan 1979 Overton's lowest low was 27 deg F.(a full 12 degrees higher)
OBSERVATIONS: In 10 years the author noted that for three separate data collection points:
Overton, Echo station, and Stuart's Point, there was NO YEAR in which more than one month
experienced temperatures lower than 27 degrees F. and only four days in ten years
experienced temperatures below 25 degrees F. The coldest temperature on record for all three
stations in ten years was 22 degrees F in Jan 1974 (however only 2 days were recorded for the
entire year as being 25 degrees F. or below). For the entire year of 1974 these three locations
had only a total of 14 days which show temperatures 32 or below and the lowest of those
remaining 12 days (excluding the two days of 25 deg or lower) was only 31 degrees.
The author's observations indicate that subfreezing temps also tend to be longer in duration in
Overton than in Yuma (which is as expected). The duration of freezes is probably the most
important climatic factor between the two areas. No attempt was made to compare that type of
data. Casual frequent trips to Yuma convince the author that the "highs" during the winter days
also tend to be much more mild. While few of the "frosts" in Yuma are threatening.
Remember, even if the low in Overton is 25 deg. and the duration is 10 hours while the low in
Yuma is 32 deg. for five minutes....both locales wind up being classed as having experienced
frost in that 24 hour period. This of course tends to offset the figures so this must be duly
taken into account.
Still the data supports the idea that the climate around this very Northerly part of the Mojave is
indeed far more tolerable to the Desert Fan Palm than has repeatedly been suggested. Note
that a similar climatic bias misplaced the type locality of this plant for 107 years!(7)
Other Climate remarks:
A statement made by James Cornett mentioned earlier was that the Mojave Desert is "a region
too cold for the genus today." I would like to comment on this idea for a moment to show why I
believe this to be a provably unfair assertion.
Although at first, in context his statement appears to indicate a reference to some work of
Axelrod, other published materials by Cornett(8) indicate that he in fact, ascribes to this
somewhat misleading and provably incorrect idea(9).
In direct contradiction to this, Peter J. Mehringer may have made the most definitive arguments
regarding the Mojave's climate. In 1963 as part of the Tule Springs archaeological expedition,
his research shows that winter cold for the areas Cornett is concerned with, have remained
constant for at least 18,000 years. Aridity and precipitation however, have changed
dramatically:
"Paleoclimatic evidence for southeastern Nevada demonstrates no significant changes between
7,000 B.P. and the present, on the basis of pollen spectra. . . . Fossil pollen spectra and
Neotoma midden analyses, combined with dendrochronology (Fritts 1971), provide a consistent
history of paleo-ecological conditions of the area for the past 18,000 years. . . .Using the above
-mentioned studies for the period of 18,000 to 8,000 B. P., paleo-climatic conditions can be
characterized as follows: There was a slow transition from cooler temperatures and increased
precipitation to conditions similar to those of the present. The increase in temperature is
considered to be between 5 degrees and 10 degrees, with winter conditions remaining as they
were, and summer temperatures increased. This was accompanied by a 40% decline in
precipitation at elevations below 2100 meters." NV State Museum Archeological papers # 19
1984 -pp 36-38 (Also see: Southwest Museum Papers #8 April 1933, SW Museum Los
Angeles-by M. R. Harrington pages 167-171 for discussion supporting and elaborating on other
aspects of all of the above).
It appears from the forgoing (includes Harrington's work) that the only thing that has really
changed has been degree of aridity and availability of water in the entire region. This same
trend applies to the Colorado Desert and Coastal and Inland California with increases (not
decreases) in summer temps only. Although the available fossils are extremely ancient
compared to this recent 18,000 year period, there is no real evidence that the area was
intolerably colder for palms before that time. It appears that the demise of widespread palms
may have been an extremely ancient occurrence but that conditions were at least more favorable
as far as moisture is concerned in many parts of the Mojave and beyond as recently as 18,000
years ago.(10)
To reiterate: Since favorable winter climate has existed in prevailing Mojave locations, for as
much as 18,000 years, widespread fossil evidence of fan palms suggests that ancient inland
oceans or periods of declining availability of moisture -not cold- wiped out these ancient taxa.
Knowing the remarkable consistency winter lows have exhibited for this recent 18,000 year
period, it would be a mistake to infer that the climate in the Mojave is somehow now too cold for
Palms since Palms are now extant wherever water has been developed and wherever humans
have brought seed throughout lower elevations in the Mojave and even beyond. If one
considers that these same conditions must have also existed for most areas in the Colorado
Desert to the south (where no one could legitimately argue it has ever been too cold for this
plant), then it becomes an entirely unreasonable assertion to say the Mojave is now or ever has
been a region "too cold for palms."
Additionally, in direct contrast to anyone's assertion that the region is too cold for palms, it has
been observed by this author (over a period of nearly twenty years) that at least seven distinctly
separate palm genera and their species(11) have been thriving throughout the farthest reaches of
the Mojave desert. Although these plantings are mostly all adventive W. filifera with origins in
the early 1900's, it is the fact that these plantings may be found near the most extreme
boundaries of the Mojave in all directions which I am highlighting. In Table A(following) some
of these locations are listed. Many must be old since they were large when the author first
noted them between 1977 and 1982. From this table, one familiar with the locations can see that
they are indeed spread throughout the entire Mojave desert. Communications with people at
random throughout the different areas indicate that palms have been in many of the locations for
more than sixty years*, in some cases even one hundred+ years** and in Moapa anciently
Table A. - Localities in the Mojave and northward where palms have been observed.
Baker CA* Barstow CA* Boron CA Boulder City NV*
Bunkerville NV* Echo Bay NV Furnace Creek CA* Glendale NV*
Grapevine Spring CA* Henderson NV* Indian Springs NV Jean NV
Katherine's Landing AZ Kelso CA* Kingman AZ Lancaster CA
Las Vegas NV* Littlefield AZ* Logandale NV** Moapa NV
Beaver Dam AZ* Mojave CA Overton NV*** Pahrump NV
Newberry Springs CA* North Edwards CA Twenty-nine Palms CA* Victorville CA
Palmdale CA Pear Blossom CA Rosamond CA Searchlight NV
Shoshone CA* Stateline NV Tecopa CA** (China Ranch) Temple Bar AZ
St. George UT
Notes on Table A:
It should be noted that Grapevine Springs is near the extreme Northwest boundary of the
Mojave. Mojave (the town) lies as far toward the Western boundary as one can go. St. George
meanwhile extends beyond the Northeastern Borders of the Mojave. Some may class Kingman
AZ with the Colorado desert or at least Sonoran although it is actually colder than St. George
Utah, Either way Kingman could represent the extreme eastern boundary. Twenty-nine Palms
is part of the extreme Southern boundary. Interestingly, Twenty-nine Palms is apparently one of
the colder areas of the Mojave desert and this may be due to its' geographical configuration at
the bases of higher elevations. Tecopa and Shoshone (far to the north), appear to experience
warmer winters than Twenty-nine Palms.
Furthermore areas in Southern Nevada around Moapa and Overton which are about 200 to
300 meters lower in elevation than Las Vegas (and which climate appears to have been
repeatedly misrepresented) apparently experience some of the mildest winter weather of the
entire Mojave and indeed have more comparable temperatures to much of the Sonoran Desert
to the South. Perhaps it should be included or listed as a similar 'sister' desert with
drainage also to the Colorado river rather than to the Great Basin.
Conclusions Regarding Climate:
I n conclusion it should be clear first of all, that not only is Moapa a region where climate is
conducive to palms whenever there is sufficient water and other favorable factors, but
additionally as far as climate goes, the entire Mojave desert is suitable for growing Palms. The
Mojave is, as noted however, somewhat colder in Winter than most of the area around Moapa.
Clearly at least climate is not now, nor has it apparently ever been a limiting factor in the Palm's
survival and persistence in the Moapa region of southern Nevada.
End of Part 5 - 'Plant & Climate Comparisons between groves'
click here to go back to part ONE
1. "...the Mojave, a region too cold for the genus today < in reference to Palms>..." James W.
Cornett. "The Desert Fan Palm-not a Relict" San Bernardino county Museum association
quarterly vol xxxvi No. 2 summer 1989, first paragraph. (back to text)
2.
Triginofila was used by the Cahuilla and therefore it is reasonable to assume this species was
present at groves in California and simply was not mentioned by Vogl & McHargue. (source:
Palm Springs Desert Museum ) (back)
3.
Actually, if we counted Palo Verde or Cercidium we have 15 out of 17 genera since Palo
Verde is found around canyons near the area of the Hoover Dam. I am not counting it however
since that is some distance from the Palms themselves. I am also not counting the numerous
Cercidium floridum and microphyllum which are becoming common as landscape plants in
xeriscapes in Overton and Moapa although I mention it's presence here to show that it is indeed
possible to grow the plant in the area. Ironwood, Olneya tesota (also not listed in the above
references) has been used to gauge an area's climate characteristics with regard to the safety of
growing citrus in Southern California. Ironwood may be found in the landscapes around in Las
Vegas which is some 100 to 300 meters higher in elevation than most of the areas around
Moapa. Furthermore, I can testify that an Orange tree grew well, produced bumper crops of
oranges and even grew taller than a certain house in Logandale for over thirty years which
substantiates that citrus even in a "cold-sink" like Logandale not only survives but may in fact do
well around the Moapa region. (back)
4.
(the type locality may be in near Overton if derived from Fremont's description. Remember
however, Fremont never explored the area around Moapa thoroughly except for a very hurried
visit which apparently missed much of the area.) (back)
5.
Logandale interestingly, was the location where Cornett collected his information about the
Winter lows of that area.: James Cornett, [pers. com.] (back)
6.
Although Jeanne Clark on page 32 of Nevada State Museum anthropological papers no. 19
states that the area has only 275 frost free days on average I have found absolutely no hard
local data to support this vastly conflicting assertion. (Yet this has been repeatedly used as
reference.) This incredibly high number of average days per year with temps 32 deg F. or lower
amounts to three full months of daily average frost episodes per year. The author lived in the
area and collection of frost data was one extremely important pursuit. Much time was spent at
the county extension in Overton pouring over frost data, If frost incidence had ever been so
high it would have most certainly have been noted. One possibility is that Las Vegas rather
than local data was used under the incorrect assumption that it was all the same. Another
possibility is that average temps for Barstow or other far colder Mojave locales were used or
lumped together with Moapa...all of which are quite different from each other with respect to
frost data, elevation and plant communities. The author's observation is that the Moapa valley's
bear far more resemblance to Sonoran communities than to other Upper Mojave communities to
the south with respect to all aspects of Flora, Fauna, Climatological and elevation
considerations. In fact, the author would suggest that the Moapa drainage is actually a very
small and isolated portion of the larger Colorado Desert community to the south with only
insignificantly cooler winters. . . (Logandale of course being a possible exception to this as
noted.) (back)
7.
Arizona's Own Palm: Washingtonia filifera - Desert Plants Vol 5, No. 3 1983 -Victor J. Miller
-University of Arizona for Boyce Thompson Arboretum. (back)
8.
"The ...expansion north suggests ...the climate has warmed to allow this species to invade."
-Cornett, James W. 1991 Population Dynamics of the Palm, Washingtonia filifera, and Global
Warming. SBCMA Quarterly 39(2) page 46. (back)
9.
This author's observation is that a theory of "Global warming" as a contributing factor in a so
called"expansion" [sic] of W. filifera northward, fails to consider important and completely
observable facts. See author's rebuttal:"W. Filifera, and Global Warming, -A
Rebuttal".-unpublished paper -1996. (back)
10.
(S.B. Parrish a California Botanist, in 1907 commenting on a specific latitude stated "this is
an area of pines not of Palms" leaving the impression that the two plant types were mutually
exclusive to habitat . This however is a broad and misleading statement since not all palms are
strictly tropical and not all pines are strictly temperate.) (back)
11.
Genera: (In general order of descending occurrence.) Washingtonia, Phoenix, Trachycarpus,
Chamaerops, Brahea, Syagrus, Sabal and Livistona. (back)
End of Part 5 - 'Plant & Climate Comparisons between groves'
click here to go back to part ONE