Anza-Borrego: Plant Guide To Borrego Palm Canyon Nature Trail

Panorama of five pictures taken on 31 January 2010 from just above the first palm grove looking down to the mouth of the Canyon (larger version). These palm trees are the remnants of a much larger grove prior to the 2004 flash flood that took out a large number of the palm trees here. See picture of ~five year old palm trees that are regenerating the former grove.

Introduction and Explanation of Plant Trail Guides

Detailed Changes To The Trail After The 9/04 Flash Flood
Highlights of This Trail
Fieldwork Dates and Summary of List Changes With Time
Botanical Trip Reports
The Plant Guide
Comments On Specific Species


This trail is the most popular one in the Anza-Borrego Desert State Park, for several good reasons. Physically, the trail is easily reached from the Visitor Center, and the trailhead is in a campground. Botanically, the trail passes through many diverse environments, offering a sampler of much of the flora of the area. The trail ends at the most treasured destination in a desert - a shady palm grove, with year-round water and a small waterfall.

However, this poor trail has been hit by flash floods two years in a row! The first one (actually apparently several of them closely spaced in time), reportedly with a 10 foot high wall of water, occurred in August 2003, destroyed the bridge on the trail and caused three other short sections to be re-routed. That flood only damaged a small number of palm trees.

The second one, on 10 September 2004, has been described as a 100 year flood, and we believe it. A 5-10 foot tall, 100 feet wide wall of water was observed at the campground, coming out of the mouth of Borrego Palm Canyon. That flood took out a large number of palm trees (~80% of the individuals in the First Grove), leaving them scattered along the lower portions of the trail, and sometimes in stacks of three palm trees angled on top of each other. Many of the trunks were broken by the force of the water, and some palm tree trunks even ended up below large boulders!

Panorama of three pictures taken on 31 January 2010, four years after the September 2004 flash flood. Also note the high water mark line of logs at left in the larger version of this photo.

This last flood wreaked havoc with two portions of this plant guide. Many of the specific plants recorded in the plant trail guide in those portions are no longer present; they have been uprooted and washed down stream. In fact, the former trail no longer exists in one area. Portions of that area have now been converted to wash, and will not have those species growing there again for some time, if ever.

A detailed discussion of the changes is given below.

The rangers and staff at Anza-Borrego Desert State Park have done a lot of work in restoring and rerouting the main trail. Most of the re-routing takes advantage of a neighboring wash, so new trail construction was kept to a minimum. See the map made from GPS recording of the old and new trail as of spring 2005. The red portion is the major reroute. There is also a minor reroute in the wash, which is too small-scale to show up on the map. [As of 2010, the new trail was extended yet farther north, and now doesn't join the old trail until the creek crossing.]

In some places, the staff had to chain-saw up numerous palm trees to open a path. In at least one place, there was a lot of deposition of other plant material as well, which had to be removed. Your feet can stay dry during the multiple crossings of the main stream, despite significant water flow, due to well-placed logs and rocks. All of us hikers are deeply grateful for all the work done to allow us such easy passage.

The destruction, while widespread, is by no means total. There are still ~20 palm trees visible in the first grove, which still is a beautiful destination. The entire alternate trail is intact and unchanged. Over two-thirds of the main trail is intact and unchanged except for scattered palm tree trunks. The rerouted main trail is easily traversed by anyone who can follow a route tagged by marking tape. [As of 2010, the new trail now just looks like the trail, and is lined with rocks in many places to make its path clear.]

Because there may yet be changes to the alignment of the trail in the future, we have left intact the guide to the trail as it was prior to 2004, including the numbering of the first occurrences of taxa found in the bypassed section. It is even quite possible that the official route will revert to the entire old trail, since it would take only a small amount of trail construction to completely restore that route.

We have added the new routes, as of 20 January 2005 and 31 January 2010, to the guide, and indicate clearly which portions of the guide are no longer on the new route. However, the guide remains primarily a description of the old route.

For species whose first occurrence was only in the superceded sections, we have begun noting their first occurrence on the new route. These occurrences are not numbered as new taxa, since each one has already been counted in the guide. However, a number of the taxa were found only in or adjacent to the washes themselves, and it may be a few years before those taxa re-appear.

In 2010, we finally realized how unique conditions were in 2004 and 2005. A lot of the species seen in those years, especially off-trail in the washes, were higher-elevation species whose seeds had been washed down in the flash floods, and that were not normally present in this area. As a result, we have moved all those species to a separate list at the end of the guide. A few of these species that had been encountered on trail are still listed in the guide with a note that it is not likely that you will see them.

This guide includes the highlights from the 1999 brochure that is sometimes available at the trailhead. The brochure is keyed to 15 numbered posts along the trail. (Note that there was an earlier 1990 brochure keyed to 18 numbered posts, some of which were at different locations and numbered differently.)

Most of those numbered posts were taken out by the 2004 flood. In many cases, a careful observer can find the stump of the post remaining, and some of the locations have marking tape with the old post number on it.

Even more confusing, in 2006 new numbered posts were added to many places, but some of them differ by one number from the post in that location previously. There is a new guide keyed to those posts available at the trailhead.

This trail guide will be, therefore, a bit challenging to follow exactly.

Historical note:

On 20 January 2005, the visitor center staff is advising people to take the alternate trail up, not the main trail. There is even a sawhorse at the trailhead which has a sign on it saying Trail washed out; use alternate trail. This recommendation is for those people who have difficulty following anything other than a well-defined trail.

We recommend that you ignore that sign and take the trail anyway unless you are not comfortable following a route that is not obvious at times, and thus requires some paying attention to divine the route. There is no actual prohibition against taking the main trail, and it looked like nearly everyone who took the alternate trail up was taking the main trail down. There is no similar sign at the top of the main trail.

That sign was removed sometime in March 2005.

Detailed Changes To The Trail After The 9/04 Flash Flood

This report is from detailed observations made on 1/24/05.

The trail and surroundings are exactly the same from mile 0.00 to mile 0.10. The trail itself is roughly, but not always exactly, the same route from mile 0.10 to mile 0.58, but the surroundings have changed dramatically in portions of that segment.

The wash itself from mile 0.10 to mile 0.13 is very different. There used to be two separate channels, with a non-wash, higher ground in-between at mile ~0.11. That higher ground is now completely gone, as are the two taxa in the guide for that location (California fagonia, Fagonia laevis, and Anderson's desert-thorn, Lycium andersonii), along with signpost 3. Thus now there is only a single, wider wash.

Second, the main wash is now closer to the trail at mile 0.14 and perhaps beyond. The water has taken a bend to its right, and chewed into the right bank of the drainage.

This has taken out the desert-willow, Chilopsis linearis ssp. arcuata, next to the catclaw, Acacia greggii, with desert mistletoe, Phoradendron californicum, as well as signpost 4. There is no longer a need for signpost 4, since its subject was the home that the desert willows made for birds.

The trail from mile 0.14 to 0.35 is shifted left of the old trail, and the stream-crossing is at a slightly-different location. The surroundings between mile 0.27 and mile 0.34 have been changed tremendously by the 9/04 flood, and many of the plant taxa were taken out by the flood. Presumably, most of those will eventually return.

Soon after the crossing of the main wash on the changed trail, at mile 0.32, there is now a new channel for the stream that must also be crossed. We had not even a mention in the guide of crossing a dry wash here before, so this is a new feature.

After that point, at mile 0.35, the trail and its environment are mostly unchanged until mile 0.46, where signpost 8 used to be. Ironically, signpost 8 said Rolling rocks. Flash floods carried these boulders here. Interestingly, the boulders are still there, but the signpost isn't! In addition, there are now palm tree trunks stacked three deep on top of boulders here.

Just beyond mile 0.46, there used to be several desert willows on the left of the trail. All are now gone except one, which has been seriously smushed. There is no sign of the cattle saltbush, Atriplex polycarpa, but unfortunately the fountain grass, Pennisetum setaceum, survived the flood.

Signpost 9 survived the flood, but the Vasey's sage, Salvia vaseyi, just beyond it did not. Even though the ground is still there, looking very similar to the way it did before, the 3-4 shrubs of this species at that location are completely gone.

At mile 0.58, the old trail is now bypassed by going up the dry wash to the right. See the map made from GPS recording of the old and new trail. The red portion is the major reroute.

However, on 1/24/05, the bypassed old trail is in surprisingly-good shape. There is only one tricky section, which may be the reason they bypassed the trail. Also, perhaps they simply thought it was a good idea to move the trail away from the main wash before it got damaged again.

The bypassed old main trail is mostly intact from mile 0.58 to mile 0.87; even signpost 10 is still present, looking untouched. The stream side of the trail is gone at mile 0.69, but the trail is easily negotiated with any danger of dropping off the side.

The major change is at mile 0.75. Formerly, the trail crossed a dry drainage. That drainage has now become the main channel, full of water seasonally! This makes the next several hundredths of a mile interesting. Once you pick your way across the water twice, you then end up on the intact old trail, with even signpost 11 undamaged.

It will be interesting to see if the now-missing species return to their former locations.

Highlights of This Trail

Number of Unique Taxa On This Trail

The following histogram gives the number of trails in our database that contain each taxon listed in the main trail guide, which does not include the higher-elevation annuals that are only seen here when washed down by infrequent flooding. We had 191 of our trails and floras in our database when this histogram was made; 53 of those trails and floras, including this one, are in Anza-Borrego State Park. A number of "1" means the taxon has only been found only on this list, among all the trails in our database.

Number of Trails
Containing A Taxon
Number Of Taxa
On This Trail
% of Taxa
On This Trail
Total Taxa179100%

We found 3 additional taxa not in the above table, since they have not been fully identified yet. The unidentified ones are marked with ?, sp or ssp in the id? column in the guide, and have no entries in the #all column.

The taxa that are unique to this trail, or found on only one other trail or flora that we have done, out of all 191 plant trail guides throughout southern California, as of 7 February 2010, are:

# trailsScientific NameCommon Name
1Astragalus nuttallianus var. cedrosensisCedros milk-vetch
1Poa bigeloviiBigelow's blue grass
2Astragalus palmeriPalmer's milk-vetch
2Chamaesyce arizonicaArizona spurge
2Chorizanthe fimbriata var. laciniatalace-fringed spineflower
2Cryptantha holopterawinged cryptantha
2Filago depressadwarf filago
2Vulpia octoflora var. hirtellahairy six-weeks fescue

This table does not include species seen only off-trail.

Fieldwork Dates and Summary of List Changes With Time

The following table gives the dates the trail was walked and taxa recorded. After each visit, the table gives the total number of taxa on the list and the breakdown of the taxa without positive identification. See Explanation of Plant Trail Guides to understand the symbols below.

Visit DateVisit ## taxa# "?"# "sp"# "~"# "ssp"

The 3/22/03 field work was an incomplete list of some of the taxa identified on a fast-paced walk. The 11/4/03 field work was only to mile 1.30. The first time the entire loop trail was covered was 11/8/03.

We did not tally the changes made on 3/14/05 separately; they were few in number since that trip was primarily to voucher some of the taxa not previously recorded for this area.

The number of qualified ids went up dramatically on 3/21/05 primarily due to a large number of new off-trail taxa. On 3/21/05, there were a total of 18 taxa found only off-trail.

The fieldwork on 11/23/05 was only to mile 0.51, and its additions were not separately recorded from those of 11/27/05.

The guide was significantly revised after the 1/28/10 fieldwork. The higher-elevation annuals that are only seen here when washed down by infrequent flooding were moved to a separate section at the end of the guide. Any species with uncertain determinations among them were removed from the list, since we may have to wait until the next 100 year flood to see them. Hence the number of species with uncertain determinations dropped dramatically, but not because more species were identified.

We thank Kay Madore for help with the 2/25/05 and 3/1/05 fieldwork, Kate Shapiro for the addition of the Crossosoma bigelovii to the guide, and Mike Crouse for help with the 1/28/10 fieldwork.

Botanical Trip Reports

17 February 2004
27 March 2004
20 January 2005
24 January 2005
25 February 2005

The Plant Guide

This is a working list, about which we make no guarantees at all until we officially release it. Use at your own risk!

See also Flora of Borrego Palm Canyon.

Version for printing, without lines and other text on this page: html (12 pages) or pdf Clickbook booklet (3 double-sided page). (See printing instructions for an explanation of these options)

miles#idCommon NameLatin Name#here#all
0.00   Begin trail near northwest end of parking lot; elevation ~835 feet (250 m).
0.00l  (Desert pupfish pond, California fan palm, Washingtonia filifera; American tule, Scirpus americanus)
0.00r  (honey mesquite, Prosopis glandulosa var. torreyana)
0.00l1 desert lavenderHyptis emoryi99 / 947
0.00b2 California suncupCamissonia californica99 / 963
0.00b3 *Mediterranean schismusSchismus barbatus99 / 952
0.00l4 desert dandelionMalacothrix glabrata50 / 718
0.00l5 California filagoFilago californica99 / 933
0.00l6 *redstem filareeErodium cicutarium99 / 984
0.00l7 pale sun-cupCamissonia pallida ssp. pallida50 / 911
0.00l  (wire-lettuce, Stephanomeria pauciflora var. pauciflora)
0.00l8 brittlebushEncelia farinosa99 / 955
0.00b9 cheesebushHymenoclea salsola var. salsola99 / 947
0.00b10 common phaceliaPhacelia distans+99 / 939
0.00l11 alkali western tansy-mustardDescurainia pinnata ssp. halictorum99 / 98
0.00b12 *London rocketSisymbrium irio99 / 924
0.00r13 desert thornappleDatura discolor+30 / 99
0.00l14 creosote bushLarrea tridentata99 / 956
0.00l  (Gander's cholla, Opuntia ganderi)
0.00l  Drinking fountain, shaded display board, trail brochures.
0.00r  Women's flush toilet
0.00r15 *red bromeBromus madritensis ssp. rubens50 / 986
0.00r16 threadstemPterostegia drymarioides20 / 947
0.00r17 *Asian mustardBrassica tournefortii99 / 947
0.00r18 hairy-podded pepper-grassLepidium lasiocarpum var. lasiocarpum99 / 932
0.00r19 desert chicoryRafinesquia neomexicana50 / 926
0.00l  Sign: "Palm Canyon Trail. [No dogs.]"
0.00r20 Fremont pincushionChaenactis fremontii99 / 913
0.00r21 popcorn flowerCryptantha intermedia99 / 938
0.00r22 Emory's rock-daisyPerityle emoryi99 / 930
0.00r  Jct. old trail to men's flush toilet
0.00r23 pygmy-weedCrassula connata+40 / 237
0.01r24 indigo bushPsorothamnus schottii10 / 948
0.01r25 strigose lotusLotus strigosus50 / 953
0.01r26 wishbone plantMirabilis bigelovii var. retrorsa30 / 930
0.01r27 sand cressCalyptridium monandrum5 / 220
0.01r28~Texas filareeErodium texanum5 / 17
0.01r29 purple-root cryptanthaCryptantha micrantha10 / 120
0.01r  Sign: "Warning: Trail is hot-dry. Carry 1 gallon of water minimum per person." (sign is meant for summer heat!)
0.01r30 brown-eyed primroseCamissonia claviformis ssp. peirsonii30 / 426
0.01r31 bearded cryptanthaCryptantha barbigera99 / 922
0.01b32 fivewing spiderlingBoerhavia intermedia99 / 910
0.02l33 six-weeks three-awnAristida adscensionis30 / 516
0.02l34 curvenut combseedPectocarya recurvata99 / 911
0.02l35 whispering bellsEmmenanthe penduliflora var. penduliflora99 / 924
0.02l36 wire-lettuceStephanomeria pauciflora var. pauciflora10 / 453
0.02l37 frost matAchyronychia cooperi2 / 28
0.02l  Sign: "Palm Grove 1.5 mi"
0.02r  (narrowleaf ditaxis, Ditaxis lanceolata; burroweed, Ambrosia dumosa)
0.02r38 big galletaPleuraphis rigida50 / 947
0.02l  Sign: "No dogs, no bicycles".
0.02l39 San Diego birdsfoot lotusLotus hamatus99 / 926
0.02r40 small-flowered poppyEschscholzia minutiflora ssp. minutiflora40 / 916
0.02r41 narrowleaf ditaxisDitaxis lanceolata99 / 933
0.03r42 Gander's chollaOpuntia ganderi20 / 941
0.03r43 Yuma spurgeChamaesyce setiloba20 / 25
0.03l44 rock hibiscusHibiscus denudatus50 / 927
0.03l45 burroweedAmbrosia dumosa50 / 952
0.03r46 California barrel cactusFerocactus cylindraceus+2 / 244
0.03l  (Pima rhatany, Krameria erecta)
0.03l47 dwarf filagoFilago depressa20 / 22
0.03l48~*sow thistleSonchus oleraceus+2 / 249
0.04l  Sign: "Mountain Lions / Rattlesnakes ..."
0.04l49 beavertail cactusOpuntia basilaris var. basilaris10 / 949
0.04l  Signpost "1" at beavertail cactus: "Don't touch! It has dozens of tiny spines that are painful to the touch and difficult to remove".
0.05l50 needle gramaBouteloua aristidoides var. aristidoides30 / 97
0.05l51 desert trumpetEriogonum inflatum+20 / 940
0.06l52 California mustardGuillenia lasiophylla10 / 19
0.06r53 small-seeded spurgeChamaesyce polycarpa50 / 955
0.06r54 chinch-weedPectis papposa var. papposa+20 / 55
0.06r55 trailing four o'clockAllionia incarnata50 / 911
0.06r56 Pima rhatanyKrameria erecta+20 / 916
0.07r57 chuparosaJusticia californica99 / 926
0.07l  Signpost "2" at ocotilla: "After a rainfall, leaves burst out within 24 hours. They'll be full grown in only five days! After a month of dry weather, the leaves fall to the ground."
0.07l58 ocotilloFouquieria splendens ssp. splendens10 / 452
0.07l59 brittle spineflowerChorizanthe brevicornu var. brevicornu10 / 332
0.09l60 thick-leaved ground cherryPhysalis crassifolia10 / 922
0.09l61 Mojave ragwortSenecio mohavensis99 / 919
0.09r62 Sonoran spurgeChamaesyce micromera3 / 15
0.09r63 wild canterbury bellsPhacelia minor+99 / 925
0.09l  (pellitory, Parietaria hespera var. hespera+)
0.09l64 star giliaGilia stellata+30 / 912
0.09r65 silver puffsUropappus lindleyi5 / 538
0.09l  Signpost "3" in 2005: "You are [about to descend into] a desert wash, a great place to look for animal tracks and scat."
0.09r66 Mormon teaEphedra aspera10 / 98
    Check for Ephedra californica later on trail
0.09r67 common fiddleneckAmsinckia menziesii var. intermedia99 / 924
0.09   Descend to cross drainage from a side canyon
0.10r68 narrow-leaved miner's lettuceClaytonia parviflora ssp. parviflora5 / 225
0.10r69 *sourcloverMelilotus indicus30 / 527
0.10b70 meally white pincushionChaenactis artemisiifolia20 / 915
0.10b  See list at end of guide of taxa that have been seen off-trail in the wash after monsoonal floods in the previous summer / fall
0.10   Cross main channel of side wash; elevation 840 feet (255 m).
0.10b71 sacred daturaDatura wrightii+10 / 330
0.10l72 sweetbushBebbia juncea var. aspera20 / 956
0.11   The area here has been greatly changed by the 10 September 2004 flash flood. Formerly, this side canyon wash had two braids, with high ground in-between. The two braids have merged, eliminating that high ground along with the old signpost "3" and some of the species.
0.11l  (foxtail barley, Hordeum murinum)
0.11   Former top of high ground between braids; the next two species were gone post 9/04 flood.
0.11l73 California fagoniaFagonia laevis+20 / 925
0.12l  Signpost "3" (pre 9/04). Cross former second braid of wash.
0.13   Ascend out of wash
0.13l74 Anderson's desert-thornLycium andersonii6 / 212
0.13r  (catclaw, Acacia greggii; prickly poppy, Argemone munita)
0.14   Trail is now shifted left from the pre 9/04 trail, but is still next to the changed main drainage with seasonal water. The sweetbush used to be on the left of the trail; it is now on the right. Note the palm trunks washed down in September 2004.
0.14r  (desert-willow, Chilopsis linearis ssp. arcuata)
0.15r75 desert bluebellsPhacelia campanularia ssp. campanularia (=P. nashiana)+30 / 47
0.16r76 *nettle-leaved goosefootChenopodium murale20 / 511
0.16r  Signpost "4" (gone post 9/04): "Hear any birds? These desert willows create a home for birds like the California quail and the Costa's hummingbird."
0.17r77 apricot mallowSphaeralcea ambigua var. ambigua10 / 922
  78 Bigelow's monkeyflowerMimulus bigelovii var. bigelovii20 / 412
0.19l  (chia, Salvia columbariae)
0.19l79 *tumble pigweedAmaranthus albus+1 / 117
0.19l80 prickly poppyArgemone munita3 / 311
0.19l81 southern California silver-lotusLotus argophyllus var. argophyllus1 / 110
0.19l82 hairy six-weeks fescueVulpia octoflora var. hirtella10 / 22
0.20r  Signpost "5" in 2005: "Follow your nose to the desert lavender bush here. Rub the leaves. The leaves change size and texture depending on soil moisture."
0.20r83 baby California fan palmWashingtonia filifera+20 / 314
0.22r84 short-winged deerweedLotus scoparius var. brevialatus3 / 338
0.23r85 fringe-podThysanocarpus curvipes10 / 216
0.25   (catclaw, Acacia greggii, with desert mistletoe, Phoradendron californicum growing on it at eye-level)
0.26l86 *California burcloverMedicago polymorpha10 / 244
0.26l87 red maidsCalandrinia ciliata1 / 125
0.27   The trail and area are greatly changed between mile 0.27 and mile 0.34. The following section of the guide is from the old trail. Presumably, many of these species will return eventually. See below for the guide to the new trail.
0.27   Guide to old trail, which no longer exists
0.27   Trail turns right 90° to cross flowing water.
0.29r  Signpost "5" (pre 9/04)
0.30r88 volcanic giliaGilia ochroleuca ssp. exilis5 / 24
0.30r89 desert tobaccoNicotiana obtusifolia2 / 222
0.30r90 common monkeyflowerMimulus guttatus5 / 124
0.30r91 southern giliaGilia australis10 / 33
0.30r92 *celeryApium graveolens1 / 16
0.30r93 *water speedwellVeronica anagallis-aquatica5 / 25
0.30r94 *common cudweedGnaphalium luteo-album2 / 222
0.30r  (lace-fringed spineflower, Chorizanthe fimbriata var. laciniata some distance down wash.)
0.30l ~(scarlet monkeyflower, Mimulus cardinalis some distance up wash)
0.30   Cross flowing water in season, stepping on rocks; elevation 885 feet (270 m). Trail then curves left 90°. Watch for bighorn sheep beginning here.
0.30r95 *white goosefootChenopodium album1 / 111
0.30r96 *rabbits-foot grassPolypogon monspeliensis3 / 139
0.27   Guide to the new trail between mile 0.27 and mile 0.34, and lists only species not found on the old trail, or found at an earlier location than previously.
0.28r97 Newberry's velvet mallowHorsfordia newberryi2 / 216
0.28l98 green miner's lettuceClaytonia parviflora ssp. viridis10 / 36
0.30r99 Payson's wild cabbageCaulanthus simulans1 / 14
0.30r100 chiaSalvia columbariae30 / 554
0.30r101 Palmer's milk-vetchAstragalus palmeri1 / 12
0.31l sp(ann Eriogonum, Eriogonum davidsonii?)11
0.32l102 catclawAcacia greggii10 / 350
0.32   Trail turns right 90° to cross flowing water.
0.32l103 *hairy rattail fescueVulpia myuros var. hirsuta5 / 121
0.34l  (fountain grass, Pennisetum setaceum; Vasey's sage, Salvia vaseyi)
0.35   Cross channel created in 2004, with seasonal flowing water
0.35   End greatly-changed area; area post-2004 flood is now mostly the same as it was before.
0.35l104 snapdragon campionSilene antirrhina20 / 39
0.35l105 Coulter's lupineLupinus sparsiflorus99 / 913
0.35l106 San Felipe dogweedAdenophyllum porophylloides5 / 530
0.35l107 white fiesta flowerPholistoma membranaceum99 / 917
0.35r  Signpost "6" (gone post 9/04): "Home to Ancient People. Morteros and metates are on boulders near here."
0.35r108 muillaMuilla maritima10 / 516
0.37r109 desert plantainPlantago ovata99 / 935
0.39l110 Parish's poppyEschscholzia parishii40 / 916
0.41r  Signpost "7" (gone post 8/03): "Note the desert varnish on these rocks."
0.41r  (California trixis, Trixis californica var. californica; in distance: desert agave, Agave deserti)
0.42l111 desert spike-mossSelaginella eremophila50 / 917
0.42   Trail is just now in shade from the mountains to the west at 2:50 pm PST on 11/4.
0.43l112 arrow-leafPleurocoronis pluriseta1 / 125
0.43l113 California trixisTrixis californica var. californica3 / 331
0.44   Trail turns left 90°
0.44b114 Vasey's sageSalvia vaseyi10 / 323
0.45   Trail turns right 90°
0.46l  Signpost "8" (gone post 9/04): "Rolling rocks. Flash floods carried these boulders here. Their nooks and crannies harbor wildlife, including pack rats and snakes". Hikers on the "Alternate Trail" can be seen just beyond the far bank of the wash.
0.47r115 cattle saltbushAtriplex polycarpa+5 / 116
0.47r116 *fountain grassPennisetum setaceum5 / 523
0.47l117 desert-willowChilopsis linearis ssp. arcuata10 / 217
0.47r118 *Oriental mustardSisymbrium orientale20 / 222
0.48l119 honey mesquiteProsopis glandulosa var. torreyana30 / 324
0.53r  Signpost "9": "You're probably being watched by desert bighorn sheep."
0.54l  Trail turns right 90°
0.56   Trail curves left 90°
0.57l  Signpost "10" in 2005: "On 'holey' ground. Tarantulas, scorpions, lizards, mice and harvest ants make many of the holes in the ground."
0.57l  (Parish's viguiera, Viguiera parishii)
0.58   Trail post 9/04 now goes straight up the drainage. Formerly, the trail curved left and crossed the drainage; elevation ~980 feet (300 m).
0.58   This section of the guide is for the old trail, which is still almost completely intact post the 9/04 flood
0.60r120 Coulter's snapdragonAntirrhinum coulterianum5 / 110
0.61r121 Wallace's woolly daisyEriophyllum wallacei1 / 17
0.61r122 prickly cryptanthaCryptantha muricata10 / 221
0.61r123 winged cryptanthaCryptantha holoptera1 / 12
0.61l124 lace-fringed spineflowerChorizanthe fimbriata var. laciniata1 / 12
0.61r  (desert nest straw, Stylocline micropoides; woolly lipfern, Cheilanthes parryi; San Felipe dogweed, Adenophyllum porophylloides)
0.62l125~iris-leaved rushJuncus xiphioides+1 / 16
0.65   Trail turns right 90° a young smoothleaf yerba santa, Eriodictyon trichocalyx var. lanatum, is found just ahead if you don't turn right
0.65r126 Wright's buckwheatEriogonum wrightii var. nodosum+5 / 222
0.65l127 boundary goldenbushEricameria brachylepis+1 / 113
0.66l128~slender-lobed four o'clockMirabilis tenuiloba5 / 56
0.66r129 woolly lipfernCheilanthes parryi20 / 530
0.66r  (slender wild oats, Avena barbata)
0.67l  The pre-2005 signpost "10", still present
0.68l  (California fan palm, Washingtonia filifera)
0.69   The left side of the trail is mostly gone post the 9/04 flood, so this spot is a bit tricky.
0.69l130 desert brickelliaBrickellia desertorum+1 / 113
0.69l  Trail jags left around boulder, but stays on this side of drainage; 3' waterfall to left
0.75   The trickiest spot post 9/04 flood. Formerly, the trail crossed a dry drainage, then curved right. That dry drainage has become the main channel. You need to cross it, then cross back in in 0.03 miles.
0.76r131spblazing starMentzelia sp. /  
0.78l132 globe giliaGilia capitata ssp. abrotanifolia1 / 112
0.79r133 ayeniaAyenia compacta2 / 211
0.80r134 Durango rootDatisca glomerata1 / 114
0.80l  desert brickelliaBrickellia desertorum2 / 2 
0.80   Cross back over stream, and rejoin old trail.
0.81l  (prickly sow thistle, Sonchus asper ssp. asper)
0.81l  (Check for Borrego milk-vetch, Astragalus lentiginosus var. borreganus)
0.81l  (deergrass, Muhlenbergia rigens)
0.82l  (mule fat, Baccharis salicifolia)
0.58   This section of the guide is for the post 9/04 trail, as marked on 1/05. This section has not been botanized much.
0.80   Junction where the new trail used to leave the wash to left. In 2010 the new trail continues straight ahead in the wash.
0.82   Jct. of old trail with the bypass route used in 2005
0.83   Trail jogs right; don't continue straight.
0.84r  (Engelmann's hedgehog cactus, Echinocereus engelmannii)
0.84r135 pebble pincushionChaenactis carphoclinia var. carphoclinia+10 / 313
0.85l136 caterpillar phaceliaPhacelia cicutaria var. hispida50 / 926
0.85l  Signpost "11": First glimpse of the Borrego Palm Canyon Oasis, a half mile ahead."
0.87l  Sign (gone post 9/04): "The Palm Oasis: a rare desert treasure." Trail jags right.
0.87r  (ironwood, Olneya tesota)
0.91l137 bajada lupineLupinus concinnus1 / 138
0.92   This was formerly a fairly flat area. The August 2003 flash flood took out the flat area to the right of the trail. The 9/04 flash flood took out the remaining shrubs there.
0.96   Jct. with new trail in 2010
0.96l138 Hooker's evening-primroseOenothera elata ssp. hirsutissima1 / 116
0.96   Go left to cross the creek just upstream of the site of the former wooden bridge.
0.96l139 floriferous monkeyflowerMimulus floribundus1 / 112
0.96r140sp*tamariskTamarix sp.1 / 15
0.96 141?baby plant like scarlet monkeyflower, Mimulus cardinalis
0.96   Cross the creek.
0.96l142 western marsh cudweedGnaphalium palustre1 / 17
0.96r143 Hall's caulanthusCaulanthus hallii3 / 15
0.97l  Jct. "Alternate Trail" (heading back to campground); Sign: "Palm Oasis (right); Alternate Trail (left); elevation ~1100 feet (335 m). Turn right
0.97r  Begin large patches of white fiesta flower, Pholistoma membranaceum
0.97   Enter shade at 2:52 p.m. on 3/27
0.97l  *sow thistleSonchus oleraceus+ /  
0.98r144 *prickly sow thistleSonchus asper ssp. asper1 / 134
0.98l  (jojoba, Simmondsia chinensis)
0.98l145 pellitoryParietaria hespera var. hespera+99 / 912
1.00l  (star-flowered bedstraw, Galium stellatum var. eremicum; desert tobacco, Nicotiana obtusifolia)
1.00l146 miner's lettuceClaytonia perfoliata ssp. perfoliata1 / 126
1.00l  Signpost "12" (washed out in 2004; replaced slightly downtrail in 2005): "Spine-tinglers: catclaw on left of trail, honey mesquite on right".
1.00l  (fish-hook cactus, Mammillaria dioica, 15 feet above the trail)
1.02l147 California bromeBromus carinatus var. carinatus10 / 351
1.05b148 Parish's viguieraViguiera parishii20 / 630
1.05l149 desert mistletoePhoradendron californicum+2 / 241
1.06l  (rock crossosoma, Crossosoma bigelovii)
1.07r  (yellow-flowered branch of chuparosa, Justicia californica)
1.09r150 climbing milkweedSarcostemma cynanchoides ssp. hartwegii3 / 313
1.15l  Signpost "13" (gone post 9/04): "Water gauge, which measures stream depth"; elevation ~1040 feet (315 m). Beginning of palm grove pre 9/04. Note the partially hidden waterfall upstream.
1.15   Short double switchback, left then right.
1.16r  Best view of the hidden waterfall.
1.19r151 scarlet spiderlingBoerhavia coccinea2 / 23
1.19l  desert tobaccoNicotiana obtusifolia /  
1.20r  Signpost "14" (gone post 9/04): "Native Shade" from the California fan palm.
1.20r  (red willow, Salix laevigata)
1.20r  First mature California fan palm pre 9/04.Washingtonia filifera /  
1.23l152sprush with round stemJuncus sp. /  
1.24   Cross the creek; elevation ~1160 feet (350 m). In December 2003, this was all choked with sand. In February 2004, the stream had cut a channel into the sand. In November 2005 it was all rocky; the sand was gone. In February 2007, it was filled with plants, mostly water cress.
1.24l153~water cressRorippa nasturtium-aquaticum10 / 117
1.24r154 *green bentgrassAgrostis viridis10 / 15
1.24r155 *Bermuda grassCynodon dactylon5 / 143
1.25   Immediately after crossing the water, the trail turns left 90°
1.26  ?Trail turns right 90° The following species, along with a small hidden pond and hidden grotto perhaps with a seasonal waterfall, are found in the moist area just across the stream to the left: unk sedge, Carex or Cyperus sp.; wrinkled rush, Juncus rugulosus; iris-leaved rush, Juncus xiphioides; rush like Juncus effusus; California loosestrife, Lythrum californicum; scarlet monkeyflower, Mimulus cardinalis; plant with leaves similar to cinquefoil, Potentilla; western sycamore, Platanus racemosa; narrowleaf willow, Salix exigua; rigid hedge-nettle, Stachys ajugoides var. rigida; southern cattail, Typha domingensis
1.26b  (arrow-weed, Pluchea sericea)
1.27   Trail turns left 90°
1.28l  boundary goldenbushEricameria brachylepis /  
1.28l  Signpost "15" (gone post 9/04; tape incorrectly says "14 location"): "Almost there...the oasis is just a few minutes ahead".
1.30l  (A roughly 5 foot waterfall. You can see a dense grove of palms ahead. California juniper, Juniperus californica, high on cliffs)
1.31b  Wright's buckwheatEriogonum wrightii var. nodosum1 / 1 
1.32l156 arrow-weedPluchea sericea5 / 213
1.32l  (Fremont cottonwood, Populus fremontii ssp. fremontii)
1.33l  (sugar bush, Rhus ovata)
1.37   A sometimes-confusing junction if the signs are gone; elevation ~1180 feet (360 m). The trail goes right, a bit uphill, not straight along the canyon bottom. Look for a post uphill to your right with an arrow pointing left. The trail going into the Palm Grove is now marked "not a through trail", and most of the Grove is blocked by barriers with signs asking you to stay out and allow the baby palms to grow up.
1.38r  Upper Trail Guide: Trail turns left 90° at the post.
1.44l  Sign: "At home in a palm oasis". After enjoying the palm grove here, turn around and go back to the jct with the Alternate Trail.
1.38   Lower Trail Guide: Cross the creek. The following species are found in the creek area below the Palm Grove. No "side" is given since the side depends where you cross.
1.38 157 Ferriss' horsetailEquisetum Xferrissii 30 / 113
1.39 158 western ragweedAmbrosia psilostachya30 / 246
1.39 159 goldenrodSolidago californica10 / 177
1.39 160 mule fatBaccharis salicifolia10 / 148
1.39 161 narrowleaf willowSalix exigua5 / 117
1.39 162 southern cattailTypha domingensis20 / 112
1.39 163~mountain California-fuchsiaEpilobium canum ssp. latifolium30 / 167
1.42 164 Fremont cottonwoodPopulus fremontii ssp. fremontii1 / 120
1.42  ~*water speedwellVeronica anagallis-aquatica /  
1.42 165 red willowSalix laevigata1 / 133
    Lower Trail Guide: Cross the creek. The following species are found in the creek area below the Palm Grove and wander into the Palm Grove, heading uphill through it. Note: this route is now closed to allow the Grove to regenerate; please respect that closure. The species found there, listed below, are common species.
1.42   Return the way you came.
1.86   Jct. Alternate Trail. Do not be worried by the trail having some uphill sections and sometimes appearing to head away from the parking lot.
1.88l  (desert lotus, Lotus rigidus)
1.89   Switchback right.
1.90   Switchback left.
1.92r  Check for Guadalupe cryptantha, Cryptantha maritima
1.95r166 beetle spurgeEuphorbia eriantha20 / 59
1.95r  Begin section of trail containing mostly caterpillar phacelia, Phacelia cicutaria var. hispida
1.95r  California fagoniaFagonia laevis /  
1.96   Switchback right.
1.97   Trail turns left 90°
1.99r167 heliotrope phaceliaPhacelia crenulata var. ambigua1 / 119
2.00l168 California cloak fernNotholaena californica+3 / 38
2.00   First local high point on trail; elevation ~1160 feet (355 m); switchback left and descend.
2.04   Cross very small drainage
2.06   Cross small drainage and begin ascending again.
2.09   ayeniaAyenia compacta /  
2.10   Second local high point on trail.
2.14   Third local high point on trail.
2.16   Fourth local high point on trail
2.16r169 California buckwheatEriogonum fasciculatum var. polifolium3 / 354
2.17r170 rattlesnake weedDaucus pusillus10 / 231
2.17r171 Coulter's lyrepodLyrocarpa coulteri var. palmeri3 / 39
2.18r172 desert twining snapdragonAntirrhinum filipes1 / 16
2.18r173 short-bannered coastal lotusLotus salsuginosus var. brevivexillus10 / 29
2.18r174 Cedros milk-vetchAstragalus nuttallianus var. cedrosensis10 / 11
2.19   Switchback right.
2.20   Trail curves left 90°
2.21 175 Arizona spurgeChamaesyce arizonica30 / 32
2.21   Fifth local high point on trail.
2.23   Sixth high point on trail. The trail is now almost flat, with a number of minor local high points
2.27r176 Guadalupe cryptanthaCryptantha maritima / 16
2.36r  Check for limestone phacelia, Phacelia cryptantha
2.38   Cross minor drainage
2.40r177 intermediate larkspurDelphinium parishii ssp. subglobosum4 / 213
2.40r  Liverworts
2.44r  A "rock bench" that you can sit on; it even has a back!
2.44r178 eucryptaEucrypta chrysanthemifolia var. bipinnatifida20 / 26
2.45   Cross minor drainage
2.48r  Check for different lupine
2.48   Cross minor drainage and ascend.
2.51   Final local high point. Now the trail stops fooling around and heads downhill toward the parking lot.
2.60r  Check for fish-hook cactus, Mammillaria dioica
2.63r179 *African daisyDimorphotheca sinuata1 / 14
2.68   Trail turns right 90°, now in wash; elevation ~940 feet (285 m).
2.68r180 Bigelow's blue grassPoa bigelovii1 / 11
2.68r181 *slender wild oatsAvena barbata1 / 149
2.70   Trail turns left 90° out of the wash.
    Check for crossosoma in rock cliffs of Alternate Wash
2.72   Long curve right 180°
2.76   Trail turns left 90° into wash.
2.77   Trail turns right 40° out of wash.
3.00l  View of ampitheatre for ranger programs.
3.03r  Sign: "Trail is hot-dry, etc.", readable only by hikers going the opposite way.
3.04   Jct paved road; turn right on it.
3.05   Enter middle of parking area for the Trail, go left to get back to the trailhead.
3.05r  ("Trailhead store")
3.10l  Desert pupfish pond.
3.10l182 American tuleScirpus americanus30 / 18
3.11   End guide back at the trailhead; elevation ~835 feet (250 m).
    Species found in winters, especially in washes after summer / fall monsoonal floods, that were seen in 2004 and 2005, sorted by scientific name, and numbered if they don't appear above either on or off-trail
    Summer / fall annuals:
  183 fringed amaranthAmaranthus fimbriatus /  
    desert thornappleDatura discolor /  
    Higher-elevation spring annuals brought down by floods:
    Coulter's snapdragonAntirrhinum coulterianum /  
  184 strigose sun-cupCamissonia strigulosa /  
    Hall's caulanthusCaulanthus hallii /  
  185 San Diego jewelflowerCaulanthus heterophyllus var. heterophyllus /  
  186 *mouse-ear chickweedCerastium glomeratum /  
    green miner's lettuceClaytonia parviflora ssp. viridis /  
  187 southern Chinese housesCollinsia concolor /  
  188 horseweedConyza canadensis /  
    Wallace's woolly daisyEriophyllum wallacei /  
  189 common bedstrawGalium aparine /  
    southern giliaGilia australis /  
    volcanic giliaGilia ochroleuca ssp. exilis /  
  190 cotton-batting plantGnaphalium stramineum /  
    *foxtail barleyHordeum murinum /  
  191 *prickly lettuceLactuca serriola /  
  192 spreading loeflingiaLoeflingia squarrosa var. squarrosa /  
    southern California silver-lotusLotus argophyllus var. argophyllus /  
  193 *white sweetcloverMelilotus albus /  
    scarlet monkeyflowerMimulus cardinalis /  
    floriferous monkeyflowerMimulus floribundus /  
  194 limestone phaceliaPhacelia affinis /  
  195 short-lobed phaceliaPhacelia brachyloba /  
    desert bluebellsPhacelia campanularia ssp. campanularia (=P. nashiana)+ /  
    caterpillar phaceliaPhacelia cicutaria var. hispida /  
    *rabbits-foot grassPolypogon monspeliensis /  
  196 tomcat cloverTrifolium willdenovii /  
  197 *brome fescueVulpia bromoides /  
    hairy six-weeks fescueVulpia octoflora var. hirtella /  
    Other species seen in 2004 and 2005:
    Palmer's milk-vetchAstragalus palmeri /  
  198 devil's spineflowerChorizanthe rigida /  
  199 desert dicoriaDicoria canescens /  
  200 Arizona lupineLupinus arizonicus /  
  201 purple matNama demissum var. demissum / 7
  202 nemacladusNemacladus sp. /  

Comments On Specific Species

Phacelia distans. This species is often misidentified as tansy-leafed phacelia, Phacelia tanacetifolia, probably because the stamens are well-exserted for both species. The stamens for Phacelia distans can be twice the length of the corolla; those for Phacelia tanacetifolia are longer.

Phacelia tanacetifolia was reported in Beauchamp as very rare in San Diego County, with only a single voucher from Coyote Canyon. Any species with only a single voucher, surrounded by many vouchers of another species, is highly suspect. The Jepson Desert Manual does not place Phacelia tanacetifolia anywhere in the Sonoran Desert. In fact, the 2001 edition of the San Diego County Plant Checklist does not place P. tanacetifolia in San Diego County. Although the 2006 edition did restore it, the presence of this species was inferred from vouchers than the authors had not seen. Tom examined those vouchers, and they are of P. distans.

Datura discolor. This annual is germinated by monsoonal summer / fall rains, and so will not be present unless such rains occurred.

Crassula connata. There are normal-looking specimens at mile 0.00, and giant, unusual specimens along the wash at mile 1.01. Astoundingly, those specimens have up to 8 flowers per 2 leaf nodes (4 leaves) = 4 flowers per node, not just 2 flowers per node! We've never seen such robust plants anyplace else.

Ferocactus cylindraceus. The varieties are not recognized in the Flora of North America treatment since they are not consistently distinguishable.

Sonchus oleraceus. A positive identification was obtained at mile 0.97.

Eriogonum inflatum . The subspecies inflatum and deflatum are bogus, and were eliminated as valid species in the 2005 Flora of North America treatment. The plants here exhibit stems that range from not inflated at all, to nearly fully inflated below nodes. The inflation apparently depends on the amount of available moisture.

Pectis papposa var. papposa. This annual is germinated by monsoonal summer / fall rains, and so will not be present unless such rains occurred. In 2005, there are only a few specimens on the main trail. Most of the plants were in the wash at the base of the alternate trail, which is the last part of this guide.

Krameria erecta. Without fruit, it is easy to misidentify these plants as K. grayi, primarily due to errors in Munz and the Jepson Manual. The color of the flowers of these plants is very similar to the flowers of K. grayi. Only the lowermost sepal is erect here, with the other sepals spreading to spreading/reflexed, so the sepals are not cupped. (The sepals do become cupped after the flowers are removed from the plant, so this may be typical of voucher specimens used for the floras.) Only the lower 0.8 mm of the 3.0 mm flag petals is fused, which is easy to miss even with a microscope. Finally, although these plants have some blunt branchlets, they also have some very spiny branchlets.

Fortunately, the fruit clearly give this identification, with barbs only along the shaft of the spines, and none at the top.

Phacelia minor. Due to misunderstandings of what the term desert means in professional floras, many people misidentify these specimens as P. campanularia ssp. vaseyformis, which is not present in the Borrego Desert. See Phacelia nashiana = P. campanularia2

Parietaria hespera var. hespera. The leaves appear to be var. hespera, but some of the calyx lobe characteristics fit var. californica. We have decided to call this variety based on the leaves. In fact, we are not at all sure that var. californica even exists.

Gilia australis, G. stellata. Both of these gilias have pinnate leaves with a narrow rachis. G. stellata has a glandular calyx and is the dominant species found along the trail; G. australis has a generally glabrous calyx, and is found only in washes. The third gilia on this trail, Gilia ochroleuca ssp. exilis, has strap-shaped leaves with a wide rachis, and is only found in washes. For pictures of how to identify the plants from this trail, see Gilias of San Diego County.

Datura wrightii. This plant died and is no longer present.

Phacelia campanularia ssp. campanularia (=P. nashiana). Tom vouchered plants from here as P. nashiana, since they fitted the Jepson Manual key and description of that species perfectly. To his utter amazement, in later work, he found that Phacelia campanularia ssp. campanularia had been incorrectly described, and that the two taxa were not actually distinct. For the full story, see Phacelia nashiana = P. campanularia2.

Chaenactis carphoclinia var. carphoclinia. Plants at mile 2.16 correspond to var. carphoclinia as defined in Munz and Beauchamp, which has pappus-paleae of central flowers 2/3 as long as corolla. Plants at mile 0.89 correspond mostly to var. attenuata, as defined in Munz and Beauchamp, which has pappus-paleae not more than 1/3 the length of the corolla. For those plants, 11 of the 13 flowers examined have the attenuate pappus; 2 of the 13 flowers have three bristles of the length of var. carphoclinia. The Jepson Manual has combined these two varieties into var. carphoclinia, which may be appropriate given the mixed nature of the pappus for the plants at mile 0.89.

Amaranthus albus, Atriplex polycarpa, Brickellia desertorum, Ericameria brachylepis, Eriogonum wrightii var. nodosum, Fagonia laevis, Washingtonia filifera. These plants were all taken out by the 9/10/04 flash flood.

Juncus xiphioides. The plants at mile 0.62 have never bloomed; the id comes from plants at mile 1.26.

Phoradendron californicum. These plants were in bloom on 2/17/04, and had a tremendously sweet, heavy fragrance then.

Notholaena californica. Surprisingly, all three occurrences of this species were dead in 2010.

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Copyright © 2003-2010 by Tom Chester, Wayne Armstrong, James Dillane and Michael Charters.
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 | Wayne Armstrong | Michael Charters
Last update: 8 February 2010 (Equisetum sp. updated 23 March 2023).