Plant Guide to
Bayside Trail, Cabrillo National Monument, San Diego

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

Some of the identifications below were based on dead plant remnants from the previous year, due to the drought in 2002 and 2004. Unfortunately, I didn't make it here in 2003 to see how the trail looks in a normal rainfall year.

The intro needs to be updated from the 2004 fieldwork.

Introduction and Explanation of Plant Trail Guides

Highlights of This Trail
Plant Communities and Floristics
Fieldwork Dates and Summary of List Changes With Time
Botanical Trip Reports
The Plant Guide
Comments On Specific Species


Cabrillo National Monument is a stunningly beautiful spot, with great views of the city of San Diego, the harbor, and the mountains. You can see the Coronado Islands in Mexico, 15-20 miles south, and north all the way to Mount San Gorgonio, ~110 miles away.

Cabrillo National Monument has a number of attractions. Of course, the star of the show is Juan Cabrillo and his "discovery" of Point Loma in 1542. The old lighthouse, built in 1854 but abandoned in 1891 for a better location under the fog layer, is in great shape and can be toured. Searchlight bunkers, control stations to direct gunfire, and gun batteries, part of the Army's defense system for San Diego Harbor, are in evidence everywhere. Tidepools are the main attraction of the eastern side of the peninsula.

For botanists, the Bayside Trail, on the east side of the peninsula, is the main attraction. This is a short, easy, beautiful trail that winds from near the Point Loma Lighthouse down the east side of Point Loma, overlooking San Diego Bay, Coronado Island, and downtown San Diego. These sights, and activity in the harbor such as the coming and going of military aircraft, cruise ships, and submarines, sometimes provide stiff competition for the plants! The trail has a remarkable number of informative signs along the way, with many illustrations identifying the plants and animals of the area.

This trail also covers some of the Point Loma Ecological Reserve, which surrounds and includes the Monument.

Directions to Cabrillo National Monument:

From southbound I-5 or westbound I-8: Take the Rosecrans Street exit. Follow Rosecrans for ~3 miles and turn right at Canon Street (there is a sign at that intersection pointing the way to Cabrillo National Monument). Follow Canon for ~a half mile west and another half mile after it curves south. Turn left onto Catalina Blvd, and take it for ~2.5 miles to the entrance station to Cabrillo National Monument. Pay your $5 at the entrance kiosk, receive the Monument Brochure with a map, and continue straight to the parking lot at the Visitor Center. The Bayside Trail begins on the east of the old Lighthouse.

From northbound I-5: take Pacific Highway to Barnett, then turn left on Rosecrans Street and follow the rest of the directions above.

Highlights of This Trail

This trail may be the best representation of what coastal California used to look like before human disturbance and the introduction of non-native plants. It is surprisingly free of non-native plants. This trail, along with the trails of Torrey Pines (see Beach Trail), have the lowest percentage of non-native plants of any of the lower-elevation trails for which Jane Strong and I have done plant guides. Moreover, this trail has fewer non-native specimens than any of the Torrey Pines trails.

Although this low percentage of non-native plants may be due to the severe drought of 2002 and 2004, I have seen many remnants of non-native grasses, as well as creeping Australian saltbush, Atriplex semibaccata, in abundance in other places at similar times. Indeed, on the ocean side of Point Loma, Atriplex semibaccata is in abundance, whereas there wasn't a single plant to be found along this trail.

I speculate that this may be due to three factors:

  1. the trail's location at the end of a peninsula, in an area dissected by canyons that has mostly escaped human contact.

  2. the control by the military of nearly all the land between this area and the mainland. The area was designated as a military reserve in 1852. This prevented that area from being used for agriculture, grazing, or, for the most part, houses with gardens, which tremendously decreased the opportunity for invasive weeds to come into this area.

    Indeed, the Bayside Trail follows an old U.S. Army roadway.

  3. an intensive effort by the U.S. Park Service to eliminate non-native plants. This is undoubtedly a large factor, and they are to be commended for actually taking action to remove non-native plants, instead of just talking about it.

    For example, here are two of their goals, under Goal Category I: Preserve Park Resources, from their fiscal year 2003 Annual Performance Plan:

    By September 30, 2005, 7.5 (50%) of 15 acres of Cabrillo NM's land impacted by exotic vegetation targeted by September 30, 1999 is contained through the removal of Carpobrotus (ice plant), acacia, eucalyptus, yellow star thistle, Russian thistle and other non-native plants.

    Ia01B1 Exotic Vegetation Species: Point Loma Ecological Reserve - By September 30, 2005, 66 (10%) of 660 acres of the Point Loma Ecological Reserve's targeted lands impacted by exotic vegetation as of FY99 are contained through the removal of acacia, Carpobrotus, eucalyptus, tree tobacco and other non-native plants.

Plant Communities and Floristics

This trail is entirely in Coastal Sage Scrub, and is so mapped in the San Diego County Vegetation Map from Tom Oberbauer, in Beauchamp (1986). Beauchamp calls it Maritime Succulent Shrub. The plants he gives as examples for its members are almost exactly the species found here.

The Trail plant list contains 50 taxa, of which 44 have so far been identified, in 1.06 unique miles of trail. Two additional taxa were confidently identified as native. Of these 46 taxa, only 6 (13%) are non-native.

I have plotted these numbers against the other trails in my database. The plots show:

Summary statistics:

By Number

LifeformNativeNon-nativeTotal Taxa
Perennial Herbs11112
Perennial Grasses303
Annual Grasses022
Annual Herbs336

By Percent

LifeformNativeNon-nativeTotal Taxa
Perennial Herbs29%17%27%
Perennial Grasses8%0%7%
Annual Grasses0%33%5%
Annual Herbs8%50%14%

Number of Unique Taxa On This Trail

The following histogram gives the number of trails in my database that contain each taxon on this trail. I had 73 trails in our database when this histogram was made; this is the only trail from Cabrillo National Monument in my database. Two other trails are at Torrey Pines, which is nearby. A number of "1" means the taxon has only been found on this trail among the trails in my database; numbers of "3" or smaller may indicate taxa found only here and at Torrey Pines.

Number of Trails
Containing A Taxon
Number Of Taxa
On This Trail
% of Taxa
On This Trail
Total Taxa44100%

I found 6 additional species not in the above table, since they have not been identified yet. The unidentified ones are marked with ? or sp in the id? column in the guide, and have no entries in the #all column.

The taxa that are truly unique, or almost unique, to this trail or area, out of the 73 trails in my database on 12 February 2004, are:

#allLatin NameCommon NameDistribution in Southern California / Distribution in Trail Guides
1Euphorbia miseracliff spurgeRARE in CA. Rocky slopes, coatsal bluffs; < 500 m. SCo, s ChI, w Dson; Baja CA.
1Atriplex canescens ssp. canescensfour-wing saltbushSCo, n TR, PR, GB, D. Note that this identification is not 100% positive yet. There is also one observation of ssp. linearis in the San Gabriel Mountains on the Brown Mountain Fireroad; and one observation at Crystal Cove on the Reef Point trail that has not been identified to subspecies yet.
2Opuntia oricolatall coast prickly pearSCo, ChI, WTR, w PR; Baja CA. Found here and at Torrey Pines.
2Agave shawiiShaw's agaveRARE in CA. s SCO (San Diego County); Baja CA. Found here and at Torrey Pines.
3Astragalus trichopodus var. lonchuscoast locoweedCoastal bluffs, fields; < 300 m. SCo, n ChI; Baja CA. Found here and at Torrey Pines.
3Cneoridium dumosumbushrues SCo, San Clemente Island; Baja CA. Found here and at Torrey Pines.

The following taxon is listed as being found only on this trail, but is not unique because it is on other trails where it has not yet been resolved to a species:

#allLatin NameCommon Name
1Carpobrotus edulis*yellow ice plant

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"

Botanical Trip Reports

9 February 2004

The Plant Guide

Version for printing, without lines and other text on this page (4 pages)

MileS#id?Common NameLatin Name#here#all
0.00   Beginning of road to Bayside Trail immediately east of Lighthouse, elevation ~400 feet.
0.00r  Sign: "Bayside Trail".
0.00r1 giant wild ryeLeymus condensatus10 / 322
0.00r2 California buckwheatEriogonum fasciculatum var. foliolosum20 / 937
0.00r3 California enceliaEncelia californica99 / 912
0.00r4 California sagebrushArtemisia californica99 / 932
0.01l  (Scrub oak, Quercus dumosa)
0.01r5sptall coast prickly pearOpuntia oricola+10 / 92
0.01r  (black sage, Salvia mellifera)
0.01r6 broom baccharisBaccharis sarothroides99 / 97
0.01r7 lemonade berryRhus integrifolia99 / 911
0.01r8~saltgrassDistichlis spicata20 / 310
0.02r9~San Diego wreathplantStephanomeria diegensis99 / 511
0.02r10 *red bromeBromus madritensis ssp. rubens5 / 136
0.06r11 chaparral bush mallowMalacothamnus fasciculatus3 / 210
0.06r  High Voltage boxes
0.07r12 cliff spurgeEuphorbia misera10 / 51
0.09r13~slender tarweedHemizonia fasciculata40 / 410
0.09r14 toyonHeteromeles arbutifolia6 / 635
0.10r15 black sageSalvia mellifera50 / 930
0.10r16 deerweedLotus scoparius var. scoparius20 / 919
0.12r17~seashore bentgrassAgrostis pallens20 / 54
0.12r18 ladies fingersDudleya edulis40 / 97
0.12r19 lanceleaf dudleyaDudleya lanceolata40 / 916
0.13r20 California-asterLessingia filaginifolia var. filaginifolia+2 / 238
0.14r21 golden yarrowEriophyllum confertiflorum var. confertiflorum20 / 940
0.15r22 coastal goldenbushIsocoma menziesii+5 / 38
0.15r23?needlegrass?Nassella sp.?5 / 2 
0.16r24 *Russian thistleSalsola tragus20 / 322
0.17l25 bicolored everlastingGnaphalium bicolor2 / 222
0.18r  (Mohave yucca, Yucca schidigera)
0.18r26spchollaOpuntia sp.3 / 3 
0.18l27~four-wing saltbushAtriplex canescens ssp. canescens1 / 11
0.21r28 *redstem filareeErodium cicutarium3 / 134
0.22l29 laurel sumacMalosma laurina1 / 129
0.23r30~coast locoweedAstragalus trichopodus var. lonchus50 / 93
0.24r31 *Mediterranean schismusSchismus barbatus5 / 111
0.24r32 *crystalline ice plantMesembryanthemum crystallinum5 / 15
0.24r33~*yellow ice plantCarpobrotus edulis1 / 11
0.24r34sppopcorn flowerCryptantha sp.1 / 1 
0.24r35?unk fleshy rosette of oblanceolate lvs.?5 / 1 
0.24r36?unk- baby slender-leaved ice plant?M. nodiflorum?1 / 1 
0.26r37 big saltbushAtriplex lentiformis ssp. lentiformis6 / 62
0.27l38 bladderpodIsomeris arborea2 / 27
0.27r  Jct. Bayside Trail itself; elevation ~315 feet. Turn left and take it. Sign: Bayside Trail, 1.2 miles". (Perhaps the 1.2 miles is the roundtrip distance, since it is ~0.7 mile to the "Trail ends" sign.)
0.29l39 Mohave yuccaYucca schidigera1 / 15
0.30r  Sign: "Dryland Pioneers" with illustrations of prickly pear, cholla, Shaw's agave, and Mohave yucca.
0.33r  Sign: "Communities", with illustrations of black sage, coastal sagebrush, cliff spurge, and chamise.
0.33r40 climbing bedstrawGalium nuttallii ssp. nuttallii3 / 316
0.37r  Sign: "Spring colors", with illustrations of morning glory vine, blue dicks, Indian paintbrush, and California encelia.
0.39r  Sign: "Weather", discussing the different communities of north- and south-facing slopes.
0.41   Trail curves left; elevation ~260 feet.
0.41r41?unk like wallflowerErysimum capitatum ssp. capitatum?1 / 1 
0.42l  Concrete and metal drain; begin posts along trail on right
0.44r  Jct. use trail.
0.46l  Concrete drain.
0.47r  Sign: "Something in the Air", with illustrations of salt bush, bladderpod, and California buckwheat.
0.48r  A very old bladderpod (Isomeris arborea).
0.50r  A green cement box; trail curves left.
0.52r  Sign: "Aliens and Natives", with illustrations of acacia, iceplant, sea dahlia and myoporum.
0.52l42 sea dahliaCoreopsis maritima5 / 14
0.52l  Building with huge doors and very wide-spaced railroad tracks (~4.5 feet apart).
0.52r43ssppurple snapdragonAntirrhinum nuttallianum ssp. nuttallianum10 / 111
0.52r44 virgin's bowerClematis lasiantha10 / 25
0.54l45 narrowleaf bedstrawGalium angustifolium ssp. angustifolium1 / 139
0.54l46 wild-cucumberMarah macrocarpus var. macrocarpus1 / 135
0.54r  Sign: "Uneasy Neighbors" discussing lichens.
0.56l  Green building with 1 door, 3 windows and 2 "storage" doors. Bench without back on right.
0.57l  Working drinking fountain. Sign on right: "Waves of Wings", with illustrations of Anna's hummingbird, wrentit, Townsend's warbler, and bushtit. Switchback right; elevation ~210 feet.
0.63r  Sign: "On the Sunny Side", with illustrations of western fence lizard, California striped racer, opossum, California whiptail, and Southern Pacific rattlesnake. Trail curves left 90°.
0.66r  Sign: "Ecology of Fire".
0.69r  Sign: "Community Service", discussing the need to preserve entire communities.
0.74r  Sign: "Local Birds", with illustrations of California quail, Bewick's wren, Rufous-sided towhee, and American kestrel.
0.75l47 bush monkeyflowerMimulus aurantiacus3 / 131
0.76l48 California polypodyPolypodium californicum20 / 214
0.78r  Sign: "Precious Water", with illustrations of toyon, scrub oak, and lemonade berry. Switchback right.
0.84r  Sign: "Nightlife", with illustrations of deer mouse, gray fox, and woodrat.
0.85r  View of Shaw's agave (Agave shawii) below the trail, with a steep use trail leading down to it. Please stay on the trail and see the one only 0.12 miles farther on the trail.
0.86r  Sign: "Small and Specialized", with illustrations of funnel-web spider, Harlequin bug, and yucca moth.
0.93l  Bench without back at a drainage; elevation ~155 feet.
0.96r  Sign: "Point Loma", discussing the history of the point, and giving the age of the sandstone as 65-75 million years.
0.97r49 Shaw's agaveAgave shawii1 / 12
0.99l ~(wartystem ceanothus, Ceanothus verrucosus)
1.00r  Sign: "Trail ends - Return by same route"; and "The Point Loma Ecological Reserve", containing 640 acres of the 1500 acres on the Point.
1.02r50 bushrueCneoridium dumosum1 / 13
1.06   Trail really ends at a big gate, signed "No Tresspassing"; elevation ~80 feet. Guide ends here; return the same way.

Comments On Specific Species

Opuntia oricola. Many of the cactus along this trail have been planted, and are young plants that are difficult to identify. All the prickly pears seem consistent with an Opuntia oricola identification, and there are many definite Opuntia oricola along the trail. I cannot rule out the presence of other prickly pear species, including a different identification for the first specimen along the trail.

Lessingia filaginifolia var. filaginifolia. This is the sensitive species San Diego sand aster, Corethrogyne filaginifolia var. incana, that was lumped into Lessingia filaginifolia var. filaginifolia in the Jepson Manual.

Isocoma menziesii. In my experience, the subspecies are not separable in Southern California. See Comments on the Jepson Manual and A Flora of Southern California by Munz: Isocoma menziesii.

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Copyright © 2002-2004 by Tom Chester.
Permission is freely granted to reproduce any or all of this page as long as credit is given to me at this source:
Comments and feedback: Tom Chester
Updated 27 February 2004.