The Coast Live Oak (Quercus agrifolia) is an iconic, majestic tree that serves as a cornerstone for wildlife and the surrounding ecosystem. It is easily-recognized by its gnarled branches and grand canopy. The Coast Live Oak flowers each spring and its acorns attract a wide variety of birds and butterflies - over 270 species rely on these trees for habitat and food.

With its rich green foliage and unique branching pattern, the Coast Live Oak is a favored choice for both residential and commercial landscapes. These resilient trees can live for centuries, often surpassing 250 years, and can grow impressively tall, reaching mature heights ranging from 30 to 80 feet.

It is one of the only California native oaks that thrives in coastal environments, it enjoys fog and mild winters. In the first year after planting, water once a week. Then, reduce it to once a month until it reaches about 10 feet tall. After that, avoid watering directly during summer.

Coast Live Oaks like to have their roots shaded. When they're young, surround them with mulch, rocks, or smaller native plants. Some California natives, such as Toyon and Manzanitas, do well as "understory" plants under the Coast Live Oak. Fallen oak leaves provide natural mulch for the tree. Don't fertilize oaks. They'll amend the soil over time with their own leaves and build the natural mycorrhizal fungus in the soil they need to thrive. Gradually, they become islands of natural fertility that improve the health of the nearby plants.

Quercus agrifolia var. agrifolia is one of two recognized varieties of this popular tree. The other variety is var. oxyadenia. Both are known as Coast Live Oak (see description of Quercus agrifolia for more details regarding the species). Differences between the two varieties and the primary species are very subtle. Var. agrifolia is found along the coast from Sonoma County southward. Gardening recommendations are the same as for Quercus agrifolia.

Quercus x alvordiana, the Alvord oak, is a hybrid oak in the genus Quercus. It has been reported to be a hybrid between Quercus douglasii and Quercus turbinella, or between Q. douglasii and Quercus john-tuckeri, which was formerly considered to be a variety of Q. turbinella. This is the most common hybrid of Q. douglasii. It is endemic to California, where it occurs in the Southern Inner California Coast Ranges and western Transverse Ranges. 'Quercus x alvordiana is a shrub or tree under 3 metres (9. 8 ft) tall which may be evergreen or deciduous. The leaves are up to 5 centimeters long, a dull blue to gray-green on top and paler green on the undersides. The leaf blades have toothed edges and some have pointed tips. The acorn is narrow in shape and up to 4 centimeters long, with a cup up to 1. 6 centimeters wide.

Scrub Oak plays a vital role in supporting biodiversity by attracting birds and a diverse range of butterflies. Its ability to thrive in various conditions and benefits to local wildlife make it a valuable addition to gardens.

It is a medium-to-small oak. Its green leaves are leathery on the surface and somewhat hairy on the underside. Scrub Oak is a versatile plant that thrives in full sun to part shade. In cooler regions, it remains compact, while in warmer areas, it spreads out and grows several meters high.

Scrub Oak benefits from a thick layer of oak leaves as mulch with a few large rocks. Refrain from summer watering to mimic its natural drought-tolerant adaptation.

Quercus cedrosensis, the Cedros Island oak, is a species of plant in the Fagaceae family. Quercus cedrosensis is native to Baja California state in northwestern Mexico, including Cedros Island. It has also been found in San Diego County, California.

Canyon live oak is a species of evergreen oak that is found in the southwestern part of North America, notably in the California Coast Ranges. It is the most wide-spread oak in the state. Its ultimate size and shade are determined by its location within the state. 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 rapid identification arises from the leaves of Canyon live oak being geometrically flat. They are often sympatric with Quercus agrifolia and several other oak species. Fossil data supports a much wider distribution throughout the western United States during the early Holocene period. Native Americans used the acorns of this species as a food staple, after leaching of the tannins; moreover, its roasted seed is a coffee substitute. After forest fires, Canyon live oak regenerates vigorously by basal sprouting, and the clonal diversity of this species has been shown to be high. Alternate common names for this taxon are Canyon oak and "Golden-Cup Oak".

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 for the 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 cornelius-mulleri is a bushy shrub not exceeding 3 meters (10 feet) in height. It is densely branched, its tangled twigs gray, brown, or yellowish, fuzzy when new and becoming scaly with age. The evergreen leaves are leathery and thick. They are bicolored: white and quite woolly on the undersides and dull gray- or yellow-green and faintly hairy on the upper surfaces. The wool on the undersides of the leaves is made up of star-shaped leaf hairs that are fused into microscopic plates. The leaf blades are oval with smooth or toothed edges, and measure 2. 5 to 3. 5 centimeters (1. 0-1. 4 inches) in length. The fruit is an acorn with a cap up to 2 centimeters (0. 8 inches) wide covered in light-colored scales and a cylindrical, round-ended nut up to 3 centimeters (1. 2 inches) long.

The majestic blue oak is a drought-tolerant deciduous tree that provides food and shelter for local wildlife. It supports birds, squirrels and insects. It is a host plant for several species of butterflies and moths.

This tree gets its name from its blue-green leaves. The bark is pale gray and textured. Blue oaks are slow-growing, but can grow to 80+ feet in height. The canopy can spread to a width of 30 feet or more. It requires a good-sized planting area and does best on dry, well-drained slopes.

Quercus dumosa is a species of plant in the Fagaceae family. This shrub/small tree goes by the common name Coastal sage scrub oak. It is found in Mexico and the United States. It is threatened by habitat loss. The species Quercus dumosa lends its name to the eponymous plant community Quercus dumosa chaparral, in which Coastal sage scrub oak and toyon often co-dominate. It is easily confused with other scrub oaks such as Quercus berberidifolia, with which it may hybridize.

This plant is an evergreen shrub growing 1 to 3 meters tall from a large, deep root network. The leaves have spiny or toothed edges. The fruit is an acorn up to 1.5 centimeters wide. Some individuals produce large crops of acorns, and some produce very few fruits. The acorns are dispersed by gravity as they fall from the tree, and by animals that pick them up, such as squirrels and jays. Animals eat them immediately or cache them for later. The acorns tend to germinate easily. Reproduction via seed generally occurs only in very moist years.

This oak grows primarily in sandy soils such as sandstone near the coast. Its habitat is often chaparral. This oak sprouts vigorously from its stump and root crown after wildfire and develops a large canopy within a few years after a fire event. It sometimes codominates with Ceanothus species as early as four years after a fire. This oak also does well in the absence of fire.

Leather oak (Quercus durata) is a small, drought-adapted oak species endemic to California. This shrub oak, in the Fagaceae (beech) family, typically grows in serpentine soils and is often found with manzanita in chaparral habitats. It thrives in mountainous regions but is well-suited for gardens as it doesn't require serpentine soil and can tolerate a variety of garden soils, including those with clay. Best adapted to dry, rocky, and nutrient-poor soils, leather oak can form low, dense thickets and is often used as an urban tree.

A keystone plant in its native ecosystem, leather oak supports a diverse range of wildlife species.

Quercus durata var. durata is the most common variety of Leather Oak. It tends to grow at elevations from 500-4900 feet, primarily in the central Coast Ranges. The other variety, var. gabrielensis, is a rare plant restricted to the Transverse Range. Leather oak is often found on serpentine soils. However, in the garden this plant does not require serpentine soil and can tolerate garden soil as well as drought and clay-rich soils. However, it is best adapted to relatively dry, rocky, nutrient-poor soil. Most individuals remain short, under 15 feet, and have small, densely organized leaves.

Engelmann oak (Quercus engelmannii) is a moderately fast-growing tree, typically evergreen but sometimes drought-deciduous in hot summers. Native to Southern California, this rare oak has lost much of its range due to suburban development. It primarily survives in San Diego County, with smaller populations in Pasadena, Orange County, southern Riverside County, and Baja California.

This oak thrives above the dry coastal plain but below 4,200 feet, where winters can be colder. Its thick, leathery blue-green leaves provide year-round color and complement gray-green landscapes. Mature trees develop stunning, gnarled trunks and wide-spreading branches, making them a striking addition to open spaces.

Engelmann oak can be tricky to grow—it prefers dry soil but stays green year-round if it has access to groundwater or nearby irrigation. It requires plenty of space, full sun, and tolerates various soil types.

As a keystone species, Engelmann oak supports an extensive array of butterflies and birds, playing a vital role in Southern California ecosystems. It pairs well with native plants like ceanothus, coffeeberry, and silktassel.

The Garry Oak (Quercus garryana), also known as Oregon White Oak or Oregon Oak, is a member of the Fagaceae family (Beeches, Chestnuts and Oaks). It has a range from the mountains of Los Angeles County northward to British Columbia, Canada, particularly in the foothills of the Siskiyou and Klamath Mountains, the Coast Ranges of Northern California, and of the west slope of the Cascades. It grows from sea level to 210 meter altitude in the northern part of its range, and at 300-1800 meter in the south of the range. There are three recognized varieties with largely overlapping ranges. The tree is named after Nicholas Garry, deputy governor of the Hudson's Bay Company, 1822-35. In the northerm part of its range it is an attractive tree, sometimes reaching 90 ft. but more often 50-60 ft. In the southern part of its range it is more often a shrub to 20 ft. It has large, lobed leaves which it drops in winter. It makes an excellent tree or shrub for mountain gardens and is important for wildlife.

Garry's Oak (Quercus garryana var. breweri) is a native tree that grows in northern, southern and central California. It tends to grow in slopes, at elevations from 2000-5900 feet.

Oregon White Oak (Quercus garryana var. garryana) is a native tree that grows in central and northern California. It tends to grow in slopes, at elevations from 1000-5900 feet.

Oregon White Oak (Quercus garryana var. semota) is a native tree that grows in northern, southern and central California. It tends to grow at elevations from 2000-5900 feet.

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 john-tuckeri is a bushy shrub growing up to 2 to 5 meters (80-200 inches or 6. 7-16. 7 feet) in height, sometimes becoming treelike, exceeding six meters (20 feet). The branches are gray or brown, the twigs coated in short woolly fibers when new and becoming scaly with age. The evergreen leaves are leathery and thick, sometimes brittle. They are gray-green, the lower surface slightly paler. The undersides are hairy, the upper surfaces somewhat less so. The leaf blade is roughly oval, spine-toothed, and less than 4 centimeters (1. 6 inches)long. The fruit is an acorn with a thin cap 1 to 1. 5 centimeters (0. 4-0. 6 inch) wide and a nut 2 to 3 centimeters (0. 8-1. 2 inches) long. Quercus john-tuckeri is a bushy shrub growing up to 2 to 5 meters (80-200 inches or 6. 7-16. 7 feet) in height, sometimes becoming treelike, exceeding six meters (20 feet). The branches are gray or brown, the twigs coated in short woolly fibers when new and becoming scaly with age. The evergreen leaves are leathery and thick, sometimes brittle. They are gray-green, the lower surface slightly paler. The undersides are hairy, the upper surfaces somewhat less so. The leaf blade is roughly oval, spine-toothed, and less than 4 centimeters (1. 6 inches)long. The fruit is an acorn with a thin cap 1 to 1. 5 centimeters (0. 4-0. 6 inch) wide and a nut 2 to 3 centimeters (0. 8-1. 2 inches) long.

The California Black Oak gets its name from the dark bark color of mature trees. It has distinctive, deeply lobed leaves that turn brilliant shades of yellow and orange in the fall. It is a large deciduous tree that can grow up to 80 feet tall. It also has a large, spreading root system.

Black Oak acorns are an important food source for a wide range of wildlife, including birds, deer, squirrels, and other mammals. It is also a host plant for butterflies and moths. It is a drought-tolerant tree with low moisture requirements. Black Oak grows best in acidic soil.

The Valley Oak (Quercus lobata) grows into the largest of North American oaks. It ranges over the hot interior valleys of California where there is a water table within reach of the roots.

Valley Oaks grow quickly, reaching 20 feet in 5 years, and 40 feet in 10 years, and up to 60 feet in 20 years. Mature specimens may attain an age of up to 600 years. Its thick, ridged bark is characteristic and evokes alligator hide. The sturdy trunk of the Valley oak may exceed two to three meters in diameter and its stature may approach 100 feet in height.

The branches have an irregular, spreading and arching appearance that produces a profound leafless silhouette in the clear winter sky. During autumn, leaves turn a yellow to light orange color but become brown during mid- to late fall.

In advancing age, the branches assume a drooping characteristic. Its pewter-colored rippled bark adds to the attractive aesthetic of this species.

Typically, leaves are five to ten centimeters in length and are roundly and deeply lobed. The leaf width is approximately one half its length. Each leaf is matte green, with a pale green underside; moreover, the leaf is covered with abundant soft fuzz, yielding an almost velvety feeling. When a fresh leaf is rubbed or broken, an aromatic scent is exuded, evoking a forest odor. The wood is a dull brown approaching yellow.

Over most of the range, acorns fall in October. A variety of mammals and birds eat them, including the Acorn Woodpecker, Western Scrub Jay, Yellow-billed Magpie, and California Ground Squirrel. Like many oaks, Valley Oaks can tolerate wildfires. Although smaller individuals may be top-killed, most resprout from the root crown.

Valley oak tolerates cool wet winters and hot dry summers but requires abundant water. It is most abundant in rich deep soils of valley floors below 600 meters in elevation but can also be found at elevations up to 5,600 ft.

Valley oak is found in dense riparian forests, open foothill woodlands and valley savannas. Commonly associated trees are Coast Live Oak, Interior Live Oak, Blue oak, Black Walnut, California Sycamore and Ghost Pine. The Valley Oak is widely distributed in the California Central Valley and many smaller valleys such as the San Fernando Valley.

Because of its eventual size, it may not be appropriate for the average residential garden. Best not to provide irrigation within 30 feet of established valley oaks. They'll often absorb too much water, causing limbs to break off.

They are messy but beautiful. Best to plant near a water source.

Quercus x macdonaldii, formerly Quercus macdonaldii, with the common names MacDonald's oak and Macdonald oak, is a rare species of oak in the Fagaceae family. The tree is endemic to the California Channel Islands, on Santa Cruz Island, Santa Rosa Island, and Santa Catalina Island, in Southern California. It is found in chaparral and woodlands habitats in canyons and slopes below 600 metres (2,000 ft). Quercus x macdonaldii is a Vulnerable species, threatened by habitat loss. Taxonomy. The plant was reclassified as Quercus x macdonaldii, a naturally occurring hybrid of Quercus berberidifolia and Quercus lobata.

Quercus pacifica is a species of oak known by the common names island scrub oak and Pacific oak. It is endemic to the Channel Islands of California, where it is known from Santa Cruz, Santa Rosa, and Santa Catalina Islands. Though limited to three islands, it is not uncommon there, occurring in grassland, chaparral, oak woodlands, forest, and other habitat. It is the dominant oak in many areas on Catalina Island.It was described as a new species in 1994 from a specimen on Santa Cruz Island.This is a shrub or a small tree growing up to five meters in height, or occasionally taller. The leaves are roughly oval in shape and edged with pointed teeth. The green blades are up to 4 centimeters long by 4 wide. They have shiny upper surfaces and waxy, hairy, glandular undersides. The acorn has a cap up to 2 centimeters wide and a nut measuring 2 or 3 centimeters long.

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, New Mexico, and in Arizona through the transition zone to the eastern Mogollon Rim, where it grows in canyons, mountain slopes, washes, and other dry habitat types. Quercus palmeri is a shrub or small tree growing up to 3 meters (10 feet) tall, but known to reach 6 meters (20 feet) at times. It branches into angular twigs and is reddish brown. The leaves are 1 to 3 centimeters (0. 4-1. 2 inches) in length. They are stiff, leathery, and brittle, their edges wavy with sharp spine-teeth. The upper surface is shiny, waxy, and olive green in color, the lower gray-green and coated with glandular hairs. The fruit is an acorn with a hairy cap up to 2. 5 centimeters (1 inch) wide and a blunt-ended nut 2 to 3 centimeters (0. 8-1. 2 inches) long. Quercus palmeri is a shrub or small tree growing up to 3 meters (10 feet) tall, but known to reach 6 meters (20 feet) at times. It branches into angular twigs and is reddish brown. The leaves are 1 to 3 centimeters (0. 4-1. 2 inches) in length. They are stiff, leathery, and brittle, their edges wavy with sharp spine-teeth. The upper surface is shiny, waxy, and olive green in color, the lower gray-green and coated with glandular hairs. The fruit is an acorn with a hairy cap up to 2. 5 centimeters (1 inch) wide and a blunt-ended nut 2 to 3 centimeters (0. 8-1. 2 inches) long. Quercus palmeri usually grows in small populations, some of which are actually cloned growths of a single plant. One such clone in the Jurupa Mountains in Riverside County, California, named the Jurupa Oak, was determined to be over 13,000 years old, a single individual living as a relict from the Pleistocene. It is therefore one of the oldest living plants in the world.

Quercus parvula is an evergreen red oak (Section Lobatae) found on north-facing Santa Cruz Island slopes and in the California Coast Ranges from Santa Barbara County north to Mendocino County. It was taxonomically combined with Quercus wislizeni until resurrected as a separate species by Kevin Nixon in 1980. The type locality is Palo Colorado Canyon in Monterey County. Three varieties of Q. parvula are currently recognized:

Quercus parvula var. shrevei, or Shreve Oak, is an evergreen red oak found in the California Coast Ranges from Santa Barbara County north to Mendocino County. It was taxonomically combined with Quercus wislizeni until resurrected as a separate species by Kevin Nixon in 1980. Recent work suggests Q. parvula var. parvula to be Q. parvula var. shrevei x Q. wislizeni.

It generally occurs in foothills where it is common in the low elevations. It is a large shrub or tree growing to 22 meters (73 feet) tall, although it seldom exceeds 10 meters (33 feet). The dark-green leaves -appearing grayish from a distance. Leaves are usually small, 2-5 cm (0. 8-2. 0 inches) long, thick, and often spiny-toothed at higher elevations. All California red oaks show evidence of introgression and/or hybridization with one another.

Quercus sadleriana is a species of oak known by the common names Sadler's oak and deer oak. It is native to southwestern Oregon and far northern California in the Klamath Mountains. It grows in coniferous forests. Quercus sadleriana is a shrub growing 1 to 3 meters (3. 3-10 feet) tall from a root network with rhizomes. The leaves are reminiscent of chestnut leaves, oval with toothed edges and rounded, faintly pointed ends. The fruit is an acorn with a cap between 1 and 2 centimeters (0. 4-0. 8 inch) wide and a spherical or egg-shaped, round-ended nut up to 2 centimeters (0. 8 inch) long. Quercus sadleriana is a shrub growing 1 to 3 meters (3. 3-10 feet) tall from a root network with rhizomes. The leaves are reminiscent of chestnut leaves, oval with toothed edges and rounded, faintly pointed ends. The fruit is an acorn with a cap between 1 and 2 centimeters (0. 4-0. 8 inch) wide and a spherical or egg-shaped, round-ended nut up to 2 centimeters (0. 8 inch) long.

Island oak (Quercus tomentella), also known as island live oak or channel islands oak, is an evergreen tree in the Oak family (Fagacea). A smaller oak tree in stature, the leaves are hairy (tomentose) on the upper and lower surfaces, toothes, and large compared to other oaks. Young twigs are also hairy, yet mature bark is gray and furrowed. Mature acorns have rounded tips and are also quite large compared to other species.

Endemic (limited) to six islands off the coast of California, it is also federally listed as a rare species because of its limited distribution in the wild. Island oak's natural habitat is Island canyons, slopes and bluffs. Oak trees support a larger number of wildlife than any type of tree in our state. Multiple mammals, birds, amphibians, and pollinators use oak trees for food and shelter. Indigenous People ground the acorns to make flour, after leaching out the tannins; they may also have roasted and ground them and used it as a coffee alternative.

In the garden it is fast growing and trouble-free. It is best used near the coast, but can tolerate inland conditions within about 20 miles of the coast if given some protection and a little extra water during dry times, especially when the young plant is getting established. The large leaves and dense shade create unfavorable conditions for understory plants; plant island shrubs and perennials with similar growing conditions next to it, rather than under it for better results.

Grey Oak (Quercus turbinella) is a rare native shrub in the Fagaceae (Oak) family that grows in scattered locations throughout the Southwestern U.S. In California it is found primarily in the Desert Mountains and Mojave Desert regions at elevations from 3900-6600 feet. The climate in these areas is wet and relatively cold in winter, dry and hot in summer. The oblong leaves are yellowish-green and the bark is grey, giving the plant an overall grey appearance.

Huckleberry Oak (Quercus vacciniifolia) is a native shrub that grows in northern, southern and central California. It is slow growing and long-lived. It grows in a semi-upright form to a height of 1.3 feet, with active growth during the spring and summer. Flowers are yellow and bloom in the early spring. Leaves are medium green, and remain on the plant throughout the year. It tends to grow in steep slopes and ridges and , at elevations from 3000-10000 feet.

Interior Live Oak (Quercus wislizeni) is a slow-growing, evergreen tree with a distinctive broad crown. The glossy dark green leaves and reddish-brown bark give it a formal look.

In winter and spring, the oak blooms with green and white flowers. The tree's long, narrow acorns serve as a food source for deer.

Interior Live Oak is a resilient and adaptable species. It thrives at elevations ranging from sea level to 5,000 feet, making it an essential part of diverse ecosystems throughout California. Interior Live Oak grows in part to full shade and prefers dry, loamy soil.

Interior Live Oak (Quercus wislizeni var. frutescens) is a native tree or shrub that grows in northern, southern and central California. It tends to grow in canyons and slopes and valleys, at elevations from 1000-6600 feet.

Interior Live Oak (Quercus wislizeni var. wislizeni) is a native tree or shrub that grows in northern, southern and central California. It tends to grow in canyons and slopes and valleys, at elevations from 0-5200 feet.