Flora of Borrego Mountain

desert five-spot, Eremalche rotundifolia, in Hawk Canyon on 28 March 2011. Left: flower. Right: calyx in fruit, with just two seeds left.
Borrego Mountain as seen from the curve just beyond mile 8.5 on the portion of S22 known as the Montezuma Grade, on 6 December 2005, on an especially clear day. See Views From the Montezuma Grade of S22 for identifications of other features in the photograph.

Procedure For Compiling the Checklist
Analysis of the Checklist
Important Caveats

Flora of Borrego Mountain

The checklist here has been updated on 10 January 2019 from eight additional field surveys; a new voucher search; and inclusion of iNaturalist observations. The text has not yet been updated.

This checklist is a start at a flora of Borrego Mountain, compiled from surveys of six different areas in 2011 and one area in 2016, and voucher records.

For this checklist, the Borrego Mountain area is defined as including San Felipe Wash as its northern boundary; SR78 as its southern boundary, with the short section of Borrego Springs Road as its western boundary, and the longitude of Benson Lake as its eastern boundary. This boundary is shown in Fig. 1, along with the locations of our surveys and of vouchers.

Fig. 1. Boundary of the Borrego Mountain Floral Area (heavy black line), and locations of the five survey areas (as of 28 March 2011, the labeled lines and cross) and vouchers (blue diamonds). Two more recent survey areas are not yet shown on this map.

The flora of Borrego Mountain has additional interest because it has some aspects of being an "Island Flora" since it is an isolated (small) range not connected to any of the surrounding mountain ranges. Borrego Mountain is surrounded by Badlands and alluvial sediment. Hence the species that live only in rugged regions, and that cannot live in alluvial areas, can't easily get here. If they do, but not too frequently, and/or their population doesn't quickly go to fairly large numbers, they can suffer extinction due to normal population fluctuations, just like a typical island flora.

For beautiful photographs of many of the species found here, and of the scenery, see the following pages by Fred Melgert and Carla Hoegen:

See also their overview map showing the routes for each of the above hikes. Borrego Mountain is in the southernmost portion of their map; zoom in there to see their hikes at Borrego Mountain.

For photographs of more than 75% of the species seen in the 7 December 2018 survey, see the iNaturalist observations from Terry Hunefeld (123 observations of 57 taxa); Don Rideout (77 observations of 52 taxa); and Birgit Knorr (53 observations of 36 taxa).

For photographs of the species seen in the 28 December 2018 survey, see the iNaturalist observations from Kate Harper, 78 observations of 64 taxa.

For photographs of the species seen in the 26 December 2018 survey by Fred Melgert and Carla Hoegen, see their iNaturalist observations, 101 observations of 36 taxa.

Procedure For Compiling The Checklist

The Checklist was compiled from field work done by the authors and from online vouchers.

Field Surveys

Seven different locations were surveyed; the locations of the first five are shown in Fig. 1, and the parameters of all the surveys for each are given in Table 1. Three of those locations were surveyed twice; the other two were surveyed a single time.

The survey areas were:

A total of 50 hours of field surveys were done on six days in January - April 2011, plus one day on 15 December 2016, by the following people:

The authors of this page are those that contributed at least 20% of the total survey time.

The parameters of the survey areas done in January - March 2011 are given in Table 1; the table does not yet includes results of the two later surveys.

Table 1. Characteristics of the Survey Areas and Number of Taxa Found

AreaDistance (miles)Survey Time (hours)# of People# of Taxa

A total of 128 taxa were found in the union of all the surveys, 121 native and 7 non-native.

Table 2 gives a breakdown of how many taxa were found in 1, 2, 3, 4 or all 5 survey areas.

Table 2. Number Of Taxa Found, Separated By The Number Of Survey Areas Containing Each Taxon

# Survey Areas# Native Taxa# Non-Native Taxa

As expected, the largest number of taxa were found in only a single survey area. However, instead of the usual continuous decline to smaller numbers with larger number of survey areas, the number of native taxa actually increases moderately toward ones found in all five survey areas. This most likely indicates a low variability in the types of habitats here. The histogram is also affected by the large difference in size between the surveyed areas, which favors preferentially finding the widespread species.

Voucher Records

The vouchers come from a search on 5 January 2011 and on 31 March 2011 of the Consortium of California Herbaria.

On 5 January 2011, the Consortium records were searched for San Diego County specimens found between latitudes of 33.15 and 33.24° and longitudes of -116.24 and -116.14°. The localities were examined and vouchers not in the Borrego Mountain area as defined above were removed.

On 31 March 2011, the Consortium records were searched for San Diego County specimens with the words Borrego and mountain in their locality field. This returned 1,904 records, which were almost entirely not in the Borrego Mountain area (with such localities as Anza-Borrego Desert State Park, Laguna Mountains Region). Only 99 vouchers were not georeferenced. Only those vouchers were examined, as a complement to the previous coordinate search. Of those, six were actually in the Borrego Mountain area.

Two vouchers were rejected as being incorrectly determined:

The final list contained 120 vouchers of 75 distinct taxa. Bill Sullivan was the dominant collector by far, with 52 vouchers, 43% of the total. Larry Hendrickson, Kim Marsden, L. Louise Jee contributed 18 vouchers, 15% of the total. Joe Barth collected 10 vouchers, 8% of the total. The remaining 40 vouchers were collected by 13 different groups.

Total Checklist

This section has not yet been updated to include results from the last two surveys.

The total checklist present below contains 140 taxa. Of those 140 taxa, 63 were both found in our survey and have vouchers from this area; 65 taxa were found only in our surveys, and 12 taxa were found only from vouchers.

The 12 taxa found only in vouchers were mostly found in areas we did not survey, especially the San Felipe Wash and lower Blow Sand Canyon / Wash area.

Analysis of the Checklist

This analysis was done on the checklist as of 30 March 2011, with names given in the Jepson Manual first edition system. It has not been redone with the results from the later surveys.

Species not found here

Since this flora is similar to an island flora, it is of interest to see what species are not found here, that are common in the surrounding area. The most common species found in our other Borrego Desert surveys, that are not found here, are given in Table 3.

Table 3. Most Common Borrego Desert species not found at Borrego Mountain

# Other Survey AreasScientific NameCommon Name
51Opuntia ganderiGander's cholla
50Opuntia basilaris var. basilarisbeavertail cactus
48Ferocactus cylindraceusCalifornia barrel cactus
38Trixis californica var. californicaCalifornia trixis
37Cheilanthes parryiwoolly lipfern
36Adenophyllum porophylloidesSan Felipe dogweed
34Salvia columbariaechia

Interestingly, both ferns and cactus are on that list. The flora of Borrego Mountain has no ferns at all, and is missing two of the most widespread and abundant cactus species, Ferocactus cylindraceus and Opuntia basilaris. (Opuntia ganderi isn't expected here since it prefers wetter, cooler areas. It is replaced here by O. echinocarpa. However, we probably observed one plant in San Felipe Creek that was a wash-down from higher elevations. That isn't included in the checklist since it is hard to be certain about the determination of a single plant, and if it is O. ganderi, it is almost surely a waif.)

Species of which only a single plant was found

It is also interesting to see the somewhat-numerous species of which we found only one single plant in a single survey. They even include a single Opuntia bigelovii, which almost never comes as a single plant! In this case, it was because of the small area surveyed at SR78. There were numerous plants along Buttes Pass Road to the north, but that area wasn't included in any survey.

Just as amazing was the single plant of Erodium cicutarium we found at the parking area for The Slot. This was either a waif, from cars or hikers, or the earliest plant of an invasion to come there. It is very heartening to see the abundance of the native Erodium texanum on every survey here, along with the absence of E. cicutarium.

Interesting species pairs

The numbers in the checklist below look like an error was made for the determination of the Phacelia crenulata varieties. We found only var. minutiflora everywhere except in the West survey, where all we found was var. ambigua! But those varieties are very distinct, and no error was made.

Diversity of species here

The Borrego Mountain Area is currently the second most depauperate area in Tom's database. Table 4 gives the ratio of the number of native taxa found to that predicted for the most depauperate areas. The prediction is from a power law best fit to the number of taxa versus area for the areas for all southern California in Tom's database (number of taxa = 128 * area in square miles ^ 0.28).

As expected, low desert regions have lower species counts than island floras due to their much more extreme climate for heat, cold, and the lack of rainfall. Although the number of taxa in the Checklist will undoubtedly increase as more of Borrego Mountain is surveyed, it is unlikely to improve its ranking much on this list for those reasons.

Borrego Mountain is about twice as diverse as the Borrego Badlands since it has more habitats than the Badlands, including additional rock types. The Borrego Badlands consist entirely of young, mostly saline, sedimentary rock. That rock is also found at Borrego Mountain, where it is accompanied by ancient metamorphic bedrock, with much more vertical relief than is found in the Badlands rock formations.

Two other species-challenged areas are represented in Table 4:

Table 4. Ratio Of The Number Of Native Taxa Found To That Predicted From The Species / Area Relationship For southern California.

0.23Borrego Badlands
0.45Borrego Mountain
0.50northeast Vallecito Mountains
0.58San Clemente Island
0.59Coyote Mountain area, Borrego Springs
0.59SnGb Pine Belt (Johnston)
0.76Starfish cove / Alma Canyon / Wash
0.78high desert mtns

Of course, depauperate does not mean there aren't interesting species here, or that this is not a beautiful area! It only means it has a low number of different species.

Some of the beautiful flowers in this area are:

And there aren't many places where one can find plants of three Chorizanthe species, C. brevicornu, C. corrugata, and C. rigida, growing within inches of each other. Depauperate dry, saline areas like here are the only place that dead man's fingers, Calandrinia ambigua, grows in the Borrego Desert.

Important Caveats

As is the case for all floras, this one is undoubtedly incomplete. It is clear from Fig. 1 that many areas of Borrego Mountain have not yet been surveyed, including the entire East Butte, the lower part of Blow Sand Canyon and Borrego Mountain Wash, several drainages on the northwest side of West Butte, and most of the San Felipe Wash below Borrego Springs Road.

In addition, it is likely that even the surveyed areas are incomplete. Table 5 gives the number of taxa found in the three areas that were surveyed twice, 2.0 to 2.5 months apart.

Table 5. Number of Taxa Found in Repeated Surveys.

Survey AreaDate# Taxa each SurveyCumulative # Taxa total from all surveys
West6 January 20118585
West8 March 201194102
Hawk11 January 20116868
Hawk28 March 20118488
North11 January 20116464
North28 March 201161*76

* The survey of the North base of Borrego Mountain was of a much shorter distance on 28 March 2011, yet it still added 12 species to its flora.

It is quite clear from Table 5 that it is unlikely we've recorded all the species in each of those areas. Surveys at different times of year, and in different years, find different species.

Finally, the numbers of some annual species may be too low in some cases. Since our surveys were all done in a single year, they couldn't reflect the proper abundance of annuals that did not germinate well this year. For example, we found Oligomeris linifolia in only one location in Hawk Canyon, where there were over 100 dead plants from a previous year, and only one live one this year. Every good year is different, due to the different germination requirements of different species.

Checklist for Borrego Mountain

The checklist here has been updated on 10 January 2019 from eight additional field surveys; a new voucher search; and inclusion of iNaturalist observations. The text has not yet been updated.


An asterisk before the common name indicates a non-native species.

The column with header BW links to the photo gallery page for each species at Fred Melgert and Carla Hoegen's BorregoWildflowers site.

The column #V gives the number of vouchers from this area for each taxon.

The column #Pls gives an estimate of the minimum number of plants for each taxon observed in the union of all survey areas, up to a maximum of 99 plants. If there is a V in this column, it indicates a species that was vouchered, but not yet seen by us. If there is an iN in that column, there is an iNaturalist observations of species we haven't yet seen and that hasn't been vouchered.

For an older checklist that has the results for different areas presented separately, see Detailed Checklist.

Version for printing, without lines and other text on this page: html (5 pages); pdf Clickbook booklet (2 double-sided pages); or a pdf Clickbook booklet condensed to fit on 1 double-sided page by removing the overall header and the clade headers. (See printing instructions for an explanation of these options)

#FamScientific Name
Link goes to the Jepson eflora
(*)Common Name
Link goes to Calphotos
1EphEphedra californicadesert teaBW15
2AcaJusticia californicachuparosaBWV
3AmaAmaranthus albus*tumble pigweedBWV
4AmaAmaranthus blitoides*mat amaranthBW5
5AmaAmaranthus fimbriatusfringed amaranthBW2
6AmaTidestromia suffruticosa var. oblongifoliaArizona honeysweetBW5
7ApoAsclepias subulatarush milkweedBW36
8ApoFunastrum hirtellumrambling milkweedBW55
9ApoPilostyles thurberiThurber's pilostylesBWV
10AstAmbrosia dumosaburroweedBW99
11AstAmbrosia salsola var. salsolacheesebushBW99
12AstBaileya pauciradiataColorado Desert marigoldBW21
13AstBebbia juncea var. asperasweetbushBW99
14AstCalycoseris wrightiiwhite tackstemBW99
15AstChaenactis carphoclinia var. carphocliniapebble pincushionBW99
16AstChaenactis fremontiiFremont pincushionBW1
17AstChaenactis stevioidesdesert pincushionBW99
18AstDicoria canescensdesert dicoriaBW99
19AstEncelia farinosabrittlebushBW99
20AstEncelia farinosa var. farinosabrittlebushBWV
21AstEncelia farinosa var. phenicodontapurple disk flower brittlebushBWV
22AstEncelia frutescensbutton enceliaBW99
23AstEricameria paniculatablackbanded rabbitbrushBW2
24AstGeraea canescenshairy desert-sunflowerBW99
25AstIsocoma acradenia var. acradeniaentire-leaved alkali goldenbushBW50
26AstIsocoma acradenia var. eremophilatoothed-leaved alkali goldenbushBW98
27AstLogfia depressadwarf filagoBW30
28AstLogfia filaginoidesCalifornia filagoBW99
29AstMalacothrix glabratadesert dandelionBW99
30AstMonoptilon bellioidesdesert starBW99
31AstPalafoxia arida var. aridaSpanish needleBW99
32AstPectis papposa var. papposachinch-weedBW99
33AstPerityle emoryiEmory's rock-daisyBW99
34AstPeucephyllum schottiipygmy-cedarBW21
35AstPleurocoronis plurisetaarrow-leafBW99
36AstPsathyrotes ramosissimaturtlebackBW2
37AstRafinesquia neomexicanadesert chicoryBW99
38AstSenecio mohavensisMojave ragwortBW99
39AstSonchus asper ssp. asper*prickly sow thistleBW1
40AstSonchus oleraceus*sow thistleBW2
41AstStephanomeria exigua ssp. exiguaslender wreathplantBW95
42AstStephanomeria pauciflorawire-lettuceBW52
43AstTrichoptilium incisumyellow-headBW99
44AstXylorhiza orcuttiiOrcutt's woody-asterBW41
45BigChilopsis linearis ssp. arcuatadesert-willowBW42
46BorAmsinckia tessellata var. tessellatabristly fiddleneckBW27
47BorCryptantha angustifolianarrow-leaved cryptanthaBW99
48BorCryptantha barbigera var. barbigerabearded cryptanthaBW99
49BorCryptantha costataribbed cryptanthaBW99
50BorCryptantha maritimaGuadalupe cryptanthaBW99
51BorCryptantha micrantha var. micranthared-root cryptanthaBW80
52BorCryptantha pterocaryawing-nut cryptanthaBW1
53BorEmmenanthe penduliflora var. penduliflorawhispering bellsBW99
54BorEucrypta micranthadesert eucryptaBW6
55BorHeliotropium curassavicum var. oculatumseaside heliotropeBWV
56BorNama demissa var. demissapurple matBWV
57BorPectocarya heterocarpachuckwalla pectocaryaBW99
58BorPectocarya platycarpabroad-fruited combseedBW30
59BorPectocarya recurvatacurvenut combseedBW99
60BorPhacelia crenulata var. ambiguaheliotrope phaceliaBW99
61BorPhacelia crenulata var. minutifloralittle-flowered heliotrope phaceliaBW99
62BorPhacelia distanscommon phaceliaBW99
63BorPhacelia pedicellatapedicellate phaceliaBW18
64BorTiquilia palmeriPalmer's coldeniaBW99
65BorTiquilia plicataplicate coldeniaBW99
66BraBrassica tournefortii*Sahara mustardBW99
67BraCaulanthus lasiophyllusCalifornia mustardBW50
68BraDescurainia pinnatawestern tansy-mustardBWiN
69BraDithyrea californicaspectacle-podBW99
70BraLepidium lasiocarpum ssp. lasiocarpumhairy-podded pepper-grassBW99
71BraLyrocarpa coulteriCoulter's lyrepodBW8
72BraSisymbrium irio*London rocketBW99
73BraStreptanthella longirostrislongbeak streptanthellaBW99
74CacCylindropuntia bigeloviiteddy-bear chollaBW99
75CacCylindropuntia echinocarpasilver chollaBW99
76CacCylindropuntia ganderiGander's chollaBW16
77CacCylindropuntia ramosissimapencil chollaBW2
78CacFerocactus cylindraceusCalifornia barrel cactusBW99
79CacMammillaria tetrancistradesert fish-hook cactusBW9
80CacOpuntia basilaris var. basilarisbeavertail cactusBW2
81CamNemacladus glanduliferusglandular nemacladusBW20
82CamNemacladus tenuis var. tenuisdesert threadplantBW10
83CarAchyronychia cooperifrost matBW99
84CheAtriplex canescens var. laciniataCaleb saltbushBW99
85CheAtriplex elegans var. fasciculatawheelscaleBW1
86CheAtriplex hymenelytradesert hollyBW99
87CheAtriplex polycarpacattle saltbushBW99
88CheChenopodium murale*nettle-leaved goosefootBW14
89CheMonolepis nuttallianaNuttall's poverty weedBW3
90CheSalsola paulsenii*Paulsen's Russian thistleBW7
91CleCleomella obtusifoliaMojave cleomellaBW14
92ConCuscuta californica var. papillosapapillate dodderBW22
93CucCucurbita palmatacoyote melonBW1
94EupChamaesyce micromeraSonoran spurgeBW99
95EupChamaesyce polycarpasmall-seeded spurgeBW99
96EupChamaesyce setilobastarfish (Yuma) spurgeBW2
97EupCroton californicusCalifornia crotonBW99
98EupDitaxis lanceolatanarrowleaf ditaxisBW8
99EupDitaxis neomexicanaNew Mexico ditaxisBW17
100EupStillingia spinulosaannual stillingiaBW99
101FabAcmispon maritimus var. brevivexillusshort-bannered coastal lotusBW22
102FabAcmispon strigosusstrigose lotusBW99
103FabAstragalus aridusannual desert milk-vetch 99
104FabAstragalus crotalariaeSalton milk-vetchBW32
105FabAstragalus didymocarpus var. dispermusdwarf white milk-vetchBW39
106FabAstragalus lentiginosus var. borreganusBorrego milk-vetchBW99
107FabAstragalus magdalenae var. peirsoniiPeirson's milk-vetch V
108FabDalea mollissilky daleaBW20
109FabDalea mollissimadowny daleaBW71
110FabLupinus arizonicusArizona lupineBW99
111FabLupinus shockleyidesert lupineBW9
112FabOlneya tesotaironwoodBW67
113FabProsopis glandulosa var. torreyanahoney mesquiteBW99
114FabPsorothamnus emoryiEmory's indigo-bushBW99
115FabPsorothamnus schottiiindigo bushBW99
116FabPsorothamnus spinosussmoke treeBW99
117FabSenegalia greggiicatclawBW99
118FabSenna armataspiny sennaBWV
119FouFouquieria splendens ssp. splendensocotilloBW99
120GerErodium cicutarium*redstem filareeBW99
121GerErodium texanumTexas filareeBW99
122KraKrameria bicolorwhite rhatanyBW99
123KraKrameria erectaPima rhatanyBW93
124LamHyptis emoryidesert-lavenderBW99
125LamSalvia columbariaechiaBW3
126LamSalvia vaseyiVasey's sageBW9
127LoaMentzelia albicauliswhite-stemmed blazing starBW3sp
128LoaMentzelia desertorumdesert blazing star 1?
129LoaMentzelia involucratabracted blazing starBW99
130LoaPetalonyx thurberi ssp. thurberiThurber's sandpaper-plantBW99
131MalEremalche exiliswhite mallowBW3
132MalEremalche rotundifoliadesert five-spotBW99
133MalHibiscus denudatusrock hibiscusBW25
134MalSphaeralcea ambigua var. ambiguaapricot mallowBW2
135MonCalyptridium monandrumsand cressBW5
136MonCistanthe ambiguadead man's fingersBW99
137NycAbronia villosa var. villosahairy sand-verbenaBW99
138NycAllionia incarnata var. incarnatasmall-flowered trailing four o'clockBW99
139NycBoerhavia wrightiiWright's spiderlingBW77
140NycMirabilis laevis var. retrorsaBigelow's desert four-o'clockBW99
141NycMirabilis tenuilobaslender-lobed four o'clockBWV
142OnaCamissoniopsis pallida ssp. pallidapale suncupBW30
143OnaChylismia cardiophylla ssp. cardiophyllaheartleaf suncupBW39
144OnaChylismia claviformis ssp. peirsoniibrown-eyed primroseBW99
145OnaEremothera boothii ssp. condensataBooth's evening primroseBW99
146OnaEulobus californicusCalifornia suncupBW99
147OnaOenothera deltoides ssp. deltoidesdune primroseBW99
148OroOrobanche cooperiCooper's broomrapeBW99
149PapEschscholzia minutiflora ssp. minutiflorasmall-flowered poppyBW99
150PapEschscholzia parishiiParish's poppyBW24
151PhrMimulus bigelovii var. bigeloviiBigelow's monkeyflowerBW2
152PlaMohavea confertifloraghost flowerBW99
153PlaPlantago ovatadesert plantainBW99
154PolAliciella latifolia ssp. latifoliabroad-leaf giliaBW99
155PolEriastrum eremicum ssp. eremicumdesert woolly-starBW2
156PolEriastrum harwoodiiHarwood's woolly-starBW~66
157PolGilia diegensiscoastal giliaBWV
158PolGilia stellatastar giliaBW3
159PolLangloisia setosissima ssp. setosissimabristly langloisiaBW99
160PolLoeseliastrum matthewsiidesert calicoBW99
161PolLoeseliastrum schottiiSchott's calicoBW99
162PolChorizanthe brevicornu var. brevicornubrittle spineflowerBW99
163PolChorizanthe corrugatawrinkled spineflowerBW85
164PolChorizanthe rigidadevil's spineflowerBW99
165PolEriogonum deflexum var. deflexumflat-topped buckwheatBW99
166PolEriogonum inflatumdesert trumpetBW99
167PolEriogonum thomasiiThomas' buckwheatBW99
168PolEriogonum thurberiThurber's buckwheatBWV
169PolEriogonum trichopeslittle desert trumpetBW99
170PolPterostegia drymarioidesfairy bowties, threadstemBW20
171ResOligomeris linifolialineleaf whitepuffBW99
172SolDatura discolordesert thornappleBW99
173SolNicotiana obtusifoliadesert tobaccoBW99
174SolPhysalis crassifoliathick-leaved ground cherryBW99
175TamTamarix ramosissima*saltcedarBW5
176VisPhoradendron californicumdesert mistletoeBW99
177ZygFagonia laevisCalifornia fagoniaBW44
178ZygKallstroemia californicaCalifornia caltropBW99
179ZygLarrea tridentatacreosote bushBW99
180ZygTribulus terrestris*puncture-vineBW5
181AgaAgave deserti var. desertidesert agaveBW99
182AgaHesperocallis undulatadesert lilyBW99
183PoaAristida adscensionissix-weeks three-awnBW99
184PoaBouteloua aristidoides var. aristidoidesneedle gramaBW85
185PoaBouteloua barbata var. barbatasix-weeks gramaBW55
186PoaBromus madritensis ssp. rubens*red bromeBW30
187PoaFestuca bromoides*brome fescue 40
188PoaHilaria rigidabig galletaBW99
189PoaSchismus barbatus*Mediterranean schismusBW99
190PoaSorghum bicolor*sorghumBW2

We thank Shaun Hawke for help with part of the 1/6/11 and 1/11/11 surveys, and RT Hawke for help with both those surveys; Bill Sullivan for help with part of the 1/6/11 survey; Pam Pallette for help with the 1/11/11 survey; Dylan Neubauer for help with the 4/3/11 survey; Birgit Knorr for help with the 12/7/18 survey; Beth Cobb for help with the 12/28/18 survey; and Jim Roberts for help with the 1/7/19 survey.

Voucher data provided by the participants of the Consortium of California Herbaria (ucjeps.berkeley.edu/consortium/)

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Copyright © 2011-2019 by Tom Chester, Walt Fidler, Kate Harper, Mike Crouse, Nancy Accola, Vince Balch, Don Rideout, James Dillane, Joe Woods, and Terry Hunefeld. Authors are those who have participated in at least two surveys, and are listed in declining order of the number of hours spent surveying here.
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
Last update: 10 January 2019