Flora of San Jacinto Peak, San Jacinto Mountains

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Introduction
Location
Procedure For Compiling The Checklist
Important Caveats
Checklist
Taxa Rejected From The Checklist

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Introduction

San Jacinto Peak is the tallest peak in the San Jacinto Mountains, reaching a peak elevation of 10,842 feet (3305 m). It is an unusual peak for the high mountains of southern California, since it stands on top of the roughly-pyramidal-shaped San Jacinto Mountains. All other high peaks in southern California are the high points along ridges, since our mountains have been uplifted by linear faults. The San Jacinto Mountains are different because they are the uplifted wedge near the junction of the two most prominent faults in southern California, the San Jacinto and San Andreas Faults. San Jacinto Peak stands close to the point of the wedge.

As a result, the views from the peak are extensive, since the Peak stands well above the surrounding terrain in almost all directions. Willis Lynn Jepson wrote in his botanical field journal on August 9, 1903:

From the summit of San Jacinto one has to my notion the finest outlook for unstudied comprehensiveness in all of California. One can see great distances in every direction. The mountain ranges succeed one another northeastward but one can not only overlook them but detect the vast mesas and desert plains which lie between them. And the highest range in the distance which finally shuts out the view is so far away that it gives no sense of dissatisfaction or complicating of a problem which one desires to solve as in the case of a range near at hand closing the immediate view as in the Sierras. Everything is understandable, comprehensible, to be worked out readily with the eye. We could name road, trail and mountain by aid of the contour map as readily as if the letters were spelled large on the country.

The northern slope of San Jacinto Mountain drops an amazing 9,682 feet in only 5.85 miles (2,951 m in 9.41 km), to 1,160 feet in Snow Canyon, a gradient of 1,655 feet per mile (314 m per km). The average slope over this entire distance is 31%; the uppermost slope averages an amazing 75% in the first 0.92 miles, a drop of 3,642 feet in 0.92 miles (1,110 m in 1.48 km).

San Jacinto Peak, like all high peaks, has been a magnet for botanists. Of the 25 species found in the immediate vicinity of the Peak, all but two (92%) have a voucher from the Peak itself and many of these species have multiple vouchers from there. For comparison, of the 51 species found in the Hidden Lake Drainage Area, 39 of them (76%) have a voucher from that area, and that area is also a magnet for botanists.

Although it is often said that San Jacinto Peak is the second tallest peak in southern California, that is not correct. The San Bernardino Mountains contain six taller peaks, thus San Jacinto Peak is actually the seventh tallest peak in southern California. However, most people would agree that San Jacinto Peak is the second most prominent peak in southern California, overshadowed only by Mount San Gorgonio, and the San Jacinto mountain range is indeed the second-highest mountain range in southern California.. For more information, see The Elevation and Prominence of San Jacinto Peak.

Location

The following map shows the location of San Jacinto Peak and the floral area targeted here:

The solid red line delineates the area considered here as being part of the flora of the Peak. It essentially follows the 10,400 foot elevation contour except at the saddle between San Jacinto Peak and Jean Peak, and near Miller Peak. It thus includes Folly Peak and Miller Peak, although we have not yet surveyed those areas and have found no vouchers from them.

The solid blue line delineates our survey path, which is the standard trail to the Peak from the east side. In addition, we surveyed most of the area within the 10,800 foot elevation contour.

The dashed red line is the 10,000 foot elevation contour, which encloses the highest elevation portion of the San Jacinto Mountains.

Procedure For Compiling The Checklist

The Checklist was compiled by the first author from online vouchers, from Hall's 1902 Flora of San Jacinto Mountain, and from field work done on 3 July 2008 (by all authors) and on 12 August 2007 (by a subset of the authors).

The vouchers were obtained in five ways:

• First, on 13 October 2006, an attempt was made to compile all San Jacinto Mountains vouchers by searching for all vouchers from Riverside County, using the Consortium of California Herbaria, with the word Jacinto in the locality. (See Voucher Coverage for the San Jacinto Mountain area for details.) Those vouchers with reported elevations were sorted by elevation to find vouchers from the Peak.

• Second, while digitizing the Hall's 1902 Flora of San Jacinto Mountain, records were kept of which species were found on the Peak by Hall.

• Third, in the course of the first author's work on the Flora of San Jacinto Mountain on other species, notes were kept for all taxa recorded from the Peak in vouchers.

• Fourth, on 5 July 2008, another search was made for vouchers from Riverside County, using the Consortium of California Herbaria, with the word Jacinto Peak in the locality.

• Fifth, on 5 July 2008, a separate search was done for each species in the final checklist presented below.

The species list from the vouchers was then culled to remove species names that probably do not exist at San Jacinto Peak, either because the location was not precise enough to be sure that the voucher was taken from the targeted area, or because the species determination on the voucher was unlikely to be correct. The rejected species are detailed below.

The above procedure resulted in a list of 26 species from vouchers.

The field work on 3 July 2008 and on 12 August 2007 resulted in a list of 18 species, including three species not found in the voucher list, creating a total list of 29 taxa. The additional three species are vouchered from nearby areas; just not from the specific area targeted here.

Important Caveats

Please note the following important caveats about this preliminary Checklist:

• We have not looked at any of the vouchers yet, so we cannot vouch for their determinations. We have checked only the names of the taxa to make sure it was not unreasonable for them to occur here.

• This is a very preliminary first draft Checklist, compiled quickly and without review by other knowledgeable botanists, and so well may contain bonehead errors.

Checklist for San Jacinto Peak

The Checklist is sorted first by category - ferns, dicots, and monocots - and then by family and scientific name. The Family and Scientific Name are from the Jepson Manual. An asterisk before the Common Name would indicate a non-native taxon, but all of the taxa found so far here are native.

There are two columns that follow the names for each taxa. The first column (# Plants/Locations) gives a rough estimate of the number of plants, and the number of locations for each species, for taxa seen in our field survey. Maximum values are 99 plants, and 9 locations. The main intent of this column is to indicate the species for which we found few plants or locations.

The second column (V) denotes those taxa that have vouchers from the Peak (V), or were reported in Hall 1902 as being at the Peak (H). One taxon, Cordylanthus nevinii, has V? in that column, because it is not certain that the voucher was taken from the targeted area. The voucher label says just near summit (forks of trail) - San Jacinto Peak, on a journey by Jepson from Tamarack Valley to the Peak. In our two surveys, we found this species only at significantly lower elevations, but since the voucher says near summit, we have included this species.

See also the list of rejected species given below.

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

Version for printing, without lines and other text on this page: html (2 pages) or pdf Clickbook booklet (1 double-sided page). (See printing instructions for an explanation of these options)

#	JM Family	Scientific Name	(*)Common Name	# Plants/ Locations	V
1	Dryopteridaceae	Cystopteris fragilis	brittle bladder fern		V
2	Pteridaceae	Cryptogramma acrostichoides	American parsley fern		V
3	Selaginellaceae	Selaginella watsonii	Watson's spike-moss	5/1	V
4	Pinaceae	Pinus contorta ssp. murrayana	lodgepole pine	50/9	V
5	Pinaceae	Pinus flexilis	limber pine	99/9	V
6	Brassicaceae	Draba corrugata var. saxosa	Southern California rock draba		V
7	Caprifoliaceae	Symphoricarpos rotundifolius var. parishii	Parish's snowberry	5/5	V
8	Caryophyllaceae	Silene parishii	Parish's campion	3/3	V
9	Fabaceae	Lupinus hyacinthinus	San Jacinto lupine	20/9	V
10	Fagaceae	Chrysolepis sempervirens	bush chinquapin	30/9	V
11	Grossulariaceae	Ribes cereum var. cereum	wax currant	20/9	V
12	Grossulariaceae	Ribes montigenum	mountain gooseberry	30/9	V
13	Lamiaceae	Monardella australis	southern mountain-monardella	10/9
14	Onagraceae	Epilobium canum ssp. latifolium	mountain California-fuchsia	5/1
15	Polygonaceae	Oxyria digyna	alpine mountain-sorrel	5/1	V
16	Portulacaceae	Calyptridium monospermum	pussy paws		V
17	Portulacaceae	Calyptridium parryi var. parryi	Parry's sand cress		V
18	Ranunculaceae	Aquilegia formosa	western columbine		V
19	Ranunculaceae	Ranunculus eschscholtzii var. oxynotus	Eschscholtz's buttercup	5/1	V
20	Rosaceae	Holodiscus microphyllus var. microphyllus	mountain spray	20/5	V
21	Rubiaceae	Galium parishii	Parish's bedstraw	10/1
22	Saxifragaceae	Heuchera hirsutissima	shaggy-haired alumroot	20/9	V
23	Scrophulariaceae	Cordylanthus nevinii	Nevin's bird's beak		V?
24	Scrophulariaceae	Pedicularis semibarbata	pine lousewort	3/1	H
25	Cyperaceae	Carex feta	greensheath sedge		V
26	Cyperaceae	Carex mariposana	Mariposa sedge		V
27	Cyperaceae	Carex multicostata	many-ribbed sedge		V
28	Cyperaceae	Carex subfusca	brown sedge	99/9	V
29	Poaceae	Trisetum spicatum	spike trisetum		V

Taxa Rejected From The Checklist

Taxa Rejected Due To Uncertain Locations

The taxon name is linked to the online voucher record.

Hymenoxys acaulis var. arizonica, UC472678. There is only this single online voucher of this taxon in all of San Jacinto Mountain, from 9000-12000 ft; high mountain species, on grassy slopes, heavy soil. The elevation range is curious, since there are no elevations higher than 10,842 feet here, and the elevation of San Jacinto Peak has been well-known since before the year 1902. Furthermore, grassy slopes with heavy soil are non-existent in the area targeted here. Hence it is unlikely this voucher was collected from the area targeted here.

Amelanchier utahensis, UC472696, also has the curious reported elevation of 9000-12000 ft, but the locality is given as Mt. Tahquitz - San Jacinto Mts., so it is surely not from the area of San Jacinto Peak. Tahquitz Peak has an elevation of 8,846 feet.

Taxa Rejected Due To Probably-Incorrect Determinations

Calyptridium umbellatum, JEPS52509. This voucher was apparently last determined in 1928. Prior to Hinton's study in 1975, many specimens of C. monospermum were lumped with C. umbellatum. The species in the San Jacinto Mountains is C. monospermum.

Spraguea umbellata, UC7765. This is a yet older name for Calyptridium umbellatum, and is probably just a databasing error, since it was annotated as Calyptridium monospermum in 1972 by W. F. Hinton.

Lupinus formosus var. formosus, RSA414785, and Lupinus formosus subsp. proximus, RSA442334. These vouchers are almost surely L. hyacinthinus, a very common and widespread species at San Jacinto Mountain, which is close to L. formosus and often confused with it.

Carex preslii, UC455134. This is the only voucher of "C. preslii" in southern California; the nearest other online specimen is from northern Inyo county, some 200 miles to the north. The most common Carex at high elevations at San Jacinto Mountain is C. subfusca, which is quite close to C. preslii according to the Jepson Manual key and descriptions. We chose not to include this name until we have further confirmation of its existence here.

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Voucher data provided by the participants of the Consortium of California Herbaria (ucjeps.berkeley.edu/consortium/). We thank Brendan Crill for his help with the 3 July 2008 fieldwork, and Jane Strong for figuring out the word comprehensiveness in Jepson's handwriting for the quote above.

Go to:

• Plants of Southern California: Regional Floras