Live oak or evergreen oak is any of a number of oaks in several different sections of the genus Quercus that share the characteristic of evergreen foliage. These oaks are generally not more closely related to each other than they are to other oaks.
Quercus agrifolia, the California live oak, or coast live oak, is an evergreen live oak native to the California Floristic Province. Live oaks are so-called because they keep living leaves on the tree all year, adding young leaves and shedding dead leaves simultaneously rather than dropping dead leaves en masse in the autumn like a true deciduous tree. Coast live oaks may be shrubby, depending on age and growing location, but is generally a medium-sized tree. It grows west of the Sierra Nevada mountain range from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section of oaks.
Quercus wislizeni, known by the common name interior live oak, is an evergreen oak, highly variable and often shrubby, found in many areas of California in the United States continuing south into northern Baja California in Mexico. It generally occurs in foothills, being most abundant in the lower elevations of the Sierra Nevada, but also widespread in the Pacific Coast Ranges—where since 1980 it has been known as a separate species Quercus parvula—and the San Gabriel Mountains. It was named for its collector, Friedrich Adolph Wislizenus (1810–1889).
Quercus douglasii, known as blue oak, is a species of oak endemic to California, common in the Coast Ranges and the foothills of the Sierra Nevada. It is California's most drought-tolerant deciduous oak, and is a dominant species in the blue oak woodland ecosystem. It is occasionally known as mountain oak and iron oak.
Dudleya virens, the green liveforever or bright green dudleya, is an uncommon species of perennial, succulent plant in the family Crassulaceae, native to several coastal southern California and Baja California locations.
Quercus engelmannii, the Engelmann oak or Pasadena oak, is a species of oak in the white oak section, native to southern California and northwestern Baja California, Mexico.
Quercus chrysolepis, commonly termed canyon live oak, canyon oak, golden cup oak or maul oak, is a North American species of evergreen oak that is found in Mexico and in the western United States, notably in the California Coast Ranges. This tree is often found near creeks and drainage swales growing in moist cool microhabitats. Its leaves are a glossy dark green on the upper surface with prominent spines; a further identification arises from the leaves of canyon live oak being geometrically flat.
Eriodictyon is a genus of plants known by the common name yerba santa within the Hydrophylloideae subfamily of the borage family, Boraginaceae. They are distributed throughout the southwestern United States and Mexico.
Hesperocyparis forbesii, with the common names Tecate cypress or Forbes' cypress, is a nonflowering, seed bearing tree species of western cypress native to southwestern North America in California and Baja California. It was formerly known as Cupressus forbesii.
Quercus vacciniifolia, the huckleberry oak, is a member of the Protobalanus section of genus Quercus. It has evergreen foliage, short styles, very bitter acorns that mature in 18 months, and a woolly acorn shell interior.
Isocoma menziesii is a species of flowering plant in the family Asteraceae, known by the common name Menzies' goldenbush.
The California coastal sage and chaparral is a Mediterranean forests, woodlands, and scrub ecoregion, defined by the World Wildlife Fund, located in southwestern California and northwestern Baja California (Mexico). It is part of the larger California chaparral and woodlands ecoregion. The ecoregion corresponds to the USDA Southern California ecoregion section 261B, and to the EPA Southern California/Northern Baja Coast ecoregion 8.
Quercus cornelius-mulleri is a North American species of oak known by the common name Muller oak, or Muller's oak. It was described to science in 1981 when it was segregated from the Quercus dumosa complex and found to warrant species status of its own. It was named after ecologist Cornelius Herman Muller. It is native to southern California and Baja California, where it grows in chaparral, oak woodlands, and other habitat in foothills and mountains. It can most easily be observed in Joshua Tree National Park and in the woodlands along the western margins of the Colorado Desert in San Diego County, California.
Quercus john-tuckeri is a North American species of oak known by the common name Tucker oak, or Tucker's oak. It is endemic to California, where it grows in the chaparral and oak woodlands of mountain slopes in the western Transverse Ranges, the southernmost Central Coast Ranges, and the margins of the Mojave Desert. The species is named after John M. Tucker, professor of botany (1947–1986) at the University of California at Davis, specialist in Quercus.
Quercus palmeri is a species of oak known by the common name Palmer oak, or Palmer's oak. It is native to California, Baja California, Southern Nevada, and in Arizona through the transition zone to the eastern Mogollon Rim, where it grows in canyons, mountain slopes, washes, and other dry habitats.
Quercus turbinella is a North American species of oak known by the common names shruboak, turbinella oak, shrub live oak, and gray oak. It is native to Arizona, California, New Mexico, Utah, Colorado, and Nevada in the western United States. It also occurs in northern Mexico.
Quercus pacifica is a species of oak known by the common names island scrub oak, Channel Island scrub oak, and Pacific oak.
Reid Venable Moran was an American botanist and the curator of botany at the San Diego Natural History Museum from 1957 to 1982.
Hesperelaea is a plant genus with only one species, probably now extinct. Hesperelaea palmeri was found only on Guadalupe Island, a small island in the Pacific Ocean, part of the Mexican state of Baja California, about 400 km (250 mi) southwest of Ensenada. The last collection of the plant on the island was in 1875, so the species and the genus must now be presumed extinct. An intensive search for the plant in 2000 was unsuccessful.
