Buck's Jewelflower [Caulanthus heterophyllus (Nutt.) Pays. var. pseudosimulans R. Buck]
Listing CNPS Unlisted R-E-D Code None
State/Federal. Status -- None BRASSICACEAE Mar.-May
Global Rank G2? State Rank S2?
Distribution: San Diego County, Riverside County, San Bernardino County, Orange County
Habitat: Chaparral and sage scrub are both utilized by Buck's Jewel Flower. This annual is a fire follower which may lie dormant as seed in areas of mature chaparral or sage scrub. Hambright gravelly clay loams are utilized in Piedre de Lumbre Canyon, and the Roblar site is mapped as Cieneba very rocky coarse sandy loam. In the Vail Lake region of western Riverside County, the habitat is a rugged Chamise Chaparral with sandy openings; on the Gavilan Plateau this vegetation is interspersed with Juniper Woodland.
Known Sites: This annual jewel flower grows abundantly on a burnt slope near Roblar Creek at Camp Pendleton, in the sage scrub one mile south of Bonsall and south of the San Luis Rey River, and on a burned north slope of Piedra de Lumbre Canyon on Camp Pendleton. It is occasional in the Vail Lake region of western Riverside County (e.g., along Highway 79 on burns) in arid sage scrub and sparse chaparral habitats; as well as on the Gavilan Plateau near Harford County Park. A few plants were seen east of Polly Butte near the City of Hemet, several colonies near Murrieta east of Antelope Road in sage scrub, as well as near Calle Azur and south of Glen Oak Valley in Riverside County. Herbarium specimens from the San Diego Natural History Museum include sites from Lilac, Monserate, Pala, and Twin Oaks Valley. Data Base entries for San Diego County show coast sites 2 miles north of Fallbrook north of the Santa Margarita River near Willow Glen Road, near the confluence of Sandia Creek and the Santa Margarita River; foothill and mountain sites for a knoll south of High Point Truck Trail east of Junction with the Cutca Trail, and Aguanga 1 mile north of Highway 79 and 1 mile west of Highway 71. A small population was observed in sage scrub upstream of the Bonsall Bridge and south of the San Luis Rey River. Riverside County reports include the Lakeview Mountains southwest of Mount Rudolph; south of Durasno Valley, from Dawson Canyon, Arroyo del Toro, and Estelle Mountain in the Gavilan Hills; the Menifee Valley; at Potrero Basin, north of the Domenighani Valley, scattered in the hills east of Massacre Canyon near Potrero, at the Motte Reserve east of Old Elsinore Road, on the west side of Crown Valley, south of Cactus Valley and Polly Butte near Hemet, north of Cactus Flat Road and east of Hemet, southeast of Lakeview, and north of Brown Canyon near Bedford Road. Reported from Orange County southeast of the Mission Vieja site and San Juan Creek; by the Data Base from the Bedford Truck Trail in the Santa Ana Mountains, and from 4.5 miles east of San Juan Capistrano in the first unnamed canyon west of Trampas Canyon on the south side of Highway 74. Data Base records from Riverside County are for the Lakeview Mountains at Mount Rudolph, 0.5 mile northwest of the Bar V Ranch, west northwest of Juniper Flat, 0.4 mile northeast of the junction of Gunther Road and Briggs Road; as well as the Motte Reserve 2.5 miles northwest of Perris, between Elsinore and Menifee, 5 miles northeast of Murrieta, the vicinity of Winchester, Bautista Canyon 7 miles east of Fairview Avenue on Highway 74, Reche Canyon 5 miles from Barton Road Turnoff on Reche Canyon Road, Aguanga approximately 1 mile north of Highway 79 and 1 mile west of Highway 71, 2.8 miles from Banning up the Idyllwild Road on the south side, and Road S-3 5 miles south of Sage.
No specimens from Baja California of this jewel flower are deposited in the San Diego Natural History Museum's herbarium.
Status: The status of Buck's Jewel Flower in San Diego County and Riverside County is presumed slowly declining, primarily due to residential development and clearance of lands for orchard. This species has substantially longer basal and cauline leaves than the related Payson's Jewel Flower. This species was unlisted by CNPS as of April 1994 because it's taxonomic description had not been adequately published; listing is expected.
Copyright © May 1994 Craig H. Reiser.