Variegated Dudleya [Dudleya variegata (Wats.) Moran]
Listing CNPS List 1B R-E-D Code 2-2-2
State/Federal. Status -- /C2 CRASSULACEAE May-Jun.
Global Rank G2 State Rank S2.2
Distribution: San Diego County; Baja California, Mexico
Habitat: Openings in sage scrub and chaparral, isolated rocky substrates in open grasslands, and a proximity to vernal pools and mima mound topography characterize habitats utilized by this small, corm-like sprouting perennial with succulent leaves. Stockpen gravelly clay loams are utilized on Otay Mesa while Redding gravelly loams are mapped for the Miramar Mounds area. Usually this Dudleya grows in small areas quite devoid of shrub cover, even though Chamise, Scrub Oak, or sage scrub elements may occur nearby.
Known Sites: A football field-sized plot with many thousands of plants was graded in 1986 at a site south of Brown Field on La Media Road. It is still found scattered across Otay Mesa (e.g., near Wruck Canyon; between Johnson and O'Neal Canyons), generally at the edges of the northern bluffs or near vernal pools. Small populations occur in Otay Valley, on Dictionary Hill, and at Miramar Mounds. Another small colony occurs west of Rolling Ridge Road and immediately south of Proctor Valley Road near Chula Vista. Herbarium specimens include the north side of La Jolla Valley 2 miles north of Santa Maria Mountain, hills near the mouth of Mission Gorge, the west side of San Miguel Mountain, 0.75 mile west of Dehesa School, on the Silver Strand, the Alva R 4-S Ranch near Black Mountain Road, Rice Canyon in Chula Vista, east of Del Mar, and near Little Cedar Canyon on Otay Mountain. Other reports are from the Sweetwater River on the west side of San Miguel Mountain, and 0.5 mile east of the junction of South Poway Parkway and Community Road. Data Base reports are for, about 0.5 mile south of Otay Valley Road and 0.75 mile east of Interstate 805 just north of Spring Canyon on the south side of Highway 117 1 mile east of its junction with Highway 75, just east of Dennery Canyon 0.75 mile north of Highway 117, near Moody Canyon south of Otay Mesa Road, the western edge of Otay Mountain about 5 miles east southeast of Brown Field, west of La Media Road near the Mexican border, numerous locales in the vicinity of Johnson Canyon and the former Brown Field Bombing Range, north of Brown Field and south of Bird Ranch near the Chester Grade, at Salt Creek about 0.8 mile northwest of Lower Otay Filtration Plant, the west side of Rock Mountain and 0.7 mile north of the Otay River, near the mouth of Wolf Canyon about 0.5 mile north of the Otay River, about 1 mile south of Otay Lakes Road between Little Cedar Canyon and Cedar Canyon on the flanks of Otay Mountain, 0.3 mile west of Little Cedar Canyon and 1.9 mile northwest of Doghouse Junction, near Minnewawa Truck Trail about 0.5 mile south of Otay Lakes Road, about 1 mile south of Highway 94 and west of Sycamore Canyon, 1.3 miles south of Otay Lakes Road and north of Sycamore Canyon, 1.5 miles south of Highway 94 and 1.1 miles west of Sycamore Canyon, 0.5 mile west of San Diego State University (where possibly extirpated), near the Sycamore Canyon Landfill on the ridgetops both east and west of Little Sycamore Canyon, 0.8 mile north of Mission Dam on the first ridge west of Spring Canyon and 1.2 miles east of Fortuna Mountain Peak, 0.2 mile east of Pomerado Road and 1.6 miles north of Poway Road, 0.5 mile east of Pomerado Road and 1.3 miles north of Poway Road, 0.5-0.6 mile east of Pomerado Road and 0.9 mile north of Poway Road, 1.2 miles north of Black Mountain road and 2.3 miles west of Highway 395, just north of Black Mountain Road and 1.7 miles west of Highway 395, 0.2 mile south of Black Mountain Road and 1.1 miles west of Highway 395, southeast of Black Mountain Road and 2 miles west of the 4-S Ranch, La Jolla Valley about 2.4 miles west of Interstate 15 on the 4-S Ranch, the west end of La Jolla Valley, northeast of the head of La Zanja Canyon and west of the San Diego Aqueduct, both one and 1.5 miles north of the Carlton Hills School near Santee, Sycamore Canyon adjacent to Camp Elliot 1.2 miles downstream from confluence with Clark Canyon Creek, ridge approximately 0.5 mile west of the Eucalyptus Hills, 1.5 miles northwest of Mother Miguel Mountain and 0.7 mile northeast of the eastern tip of Sweetwater Reservoir, 0.35-0.6 mile north northwest of San Miguel Mountain, 3.2 km south of Lake Hodges Dam, on Otay Mountain about 1.5 miles east northeast of Buschalaugh Cove on Lower Otay Lake; also at scattered locales in Proctor Valley including just east of Indian Rock Corral on the east side of Proctor Valley Road, from 0.5-1.0 mile north of the tip of Upper Otay Reservoir in the Jamul Mountains, 1.1 miles east of Proctor Valley Road in the Jamul Mountains, and 0.8 mile due north of the eastern tip of Lower Otay Reservoir. An isolated Data Base report is from the U.S. Naval Radio Station at Imperial Beach just east of the beach. Old biological survey reports note sites south of Artesian Road and north of Lusardi Creek near Camino Juan Arturo, in Poway near La Manda and Pomerado Roads, and the slopes north of the South Bay Freeway near Sweetwater Reservoir.
Eleven specimens are recorded for Baja California in the herbarium at the San Diego Natural History Museum; south to 32 5' North where collected by Moran (SD 49681) on the south side of Guadalupe Valley above the 67 km Highway marker. This dudleya was relatively common beneath shrubs on a mesa on the south side of Valle de las Palmas in Baja California, approximately 1.5 mile west of the Tecate/Ensenada Highway.
Status: Variegated Dudleya is severely declining in San Diego County. The cryptic nature of this species except during spring and early summer makes focused botanical surveys in possible habitat suspect outside these seasons. Widespread grading on Otay Mesa has recently eliminated major populations and outlying colonies. The land rush to take advantage of federal tax benefits bestowed on industrial parks adjacent to the Mexican border is the primary stimulus for this habitat loss. Despite the number of historically reported locales, recent losses indicate that all substantial populations should be protected, and that significant portions of all smaller populations should be placed into biological open space.
Sticky Dudleya [Dudleya viscida (Wats.) Moran
Listing CNPS List 1B R-E-D Code 3-2-3
State/Federal. Status -- /C1 CRASSULACEAE May-Jun.
Global Rank G2 State Rank S2.1
Distribution: San Diego County, Riverside County, and Orange County
Habitat: This conspicuous succulent perennial grows predominantly on very steep north-facing slopes. It is amenable to shade and mesic conditions. San Miguel-Exchequer rocky silt loams are utilized near Del Dios Highway and Blasingame loams are found in the northern Camp Pendleton sites. Typically, Sticky Dudleya is situated on exposed gabbroic rock, growing on very shallow soils or from cracks on vertical rock slabs.
Known Sites: A large population of well over 10,000 individuals was discovered in "Devil's Gorge", where Devil's Canyon and San Mateo Creek meet, in the northeastern corner of Camp Pendleton. Scattered populations occur on bluffs south of the San Luis Rey River in Oceanside near Lawrence Canyon and Riverside Drive. Of these populations, several are scheduled to be impacted from a CALTRANS project. A City of Oceanside project on Canyon Drive impacts another site nearby where substantial numbers will have to be transplanted upslope. Still another population on Poplar Drive immediately to the east was reportedly displaced by development and was partially transplanted to nearby locales with only fair success. Herbivory was the central problem. Additional county sites are found on steep north-facing slopes near Ysidora on Camp Pendleton, at Aliso Canyon at Camp Pendleton, and nearby on south-facing slopes north of the Santa Margarita River. At this latter site plants grow atypically in the understory of sage scrub on level terrain. Two reports are from Escondido Creek in eastern Rancho Santa Fe, and on San Marcos Creek 0.5 mile west of Rancho Santa Fe Road. The southernmost population occurs on a secluded riparian creek 1 mile west of Lake Hodges and south of Del Dios Highway and the San Dieguito River. Also reported by Roberts for Orange County in Upper Hot Springs and San Juan Canyon in the Santa Ana Mountains. An old biological survey report notes this plant along the Sitton Peak Truck Trail. A small population of several hundred plants was found in Lucas Canyon at the boundary fence of the Cleveland National Forest in Orange County. A Data Base report notes this plant in San Mateo Canyon about 0.2 mile north of Fisherman's Camp within the wilderness area for extreme southwestern Riverside County.
Status: Sticky Dudleya populations are slowly declining. Colonies south of the San Luis Rey River are not being adequately protected with dedicated biological open space and appropriate buffers. All populations should be protected.
Copyright © May 1994 Craig H. Reiser.
Back to Craig H. Reiser's Rare Plants of San Diego County