Quercus lobata Née var. insperata Jeps.

Scientific Name: Quercus lobata Née var. insperata Jeps.

Classification: Plantae/ Tracheobionta / Spermatophyta / Magnoliophyta / Magnoliopsida / Hamamelididae / Fagales / Fagaceae / Quercus L./ Quercus lobata Née var. insperata Jeps.

<i>Quercus lobata</i> Née var. insperata Jeps.
General Information
Usda SymbolQULOI
Life CyclePerennial
Growth HabitsTree
Native LocationsQULOI

Plant Guide


General: White oak is a dominant species of valley oak savanna and low elevation riparian forests in California, providing a critical habitat for many animal and plant species, stabilizing soils in flood plains, and contributing an aesthetic value to the natural landscape. Wildlife: California white oak acorns are an important food source for deer, California ground squirrels, band-tailed pigeons, and acorn woodpeckers. Ethnobotanic: Native Americans used acorns as a food staple. Economic: White oak was a source of timber by early settlers. However, because older trees are especially susceptible to fungal decay, their wood was not widely preferred.


Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status, such as, state noxious status and wetland indicator values.


General: Oak Family (Fagaceae). California white oak, sometimes referred to as valley oak, is a deciduous tree, 12 to 30 m tall, with a rounded spreading crown. The mature bark is gray, scaly, and often vertically fissured in a checker-like pattern. Leaves are oblong to obovate, 5 to 10 cm long, with 7 to 11 deep lobes. The upper surface is green and shiny; the lower surface is grayish green. Like all oaks, white oak is monoecious and wind-pollinated. The acorn cups are composed of thick, tubercled scales. The one-seeded nuts are 3 to 5 cm long, oblong to ovoid, and mature in one year. Flowering takes place from March to April. Fruits mature between August and October. Good acorn production has been reported to occur annually, but high acorn numbers occur episodically. Trees of this species may be among the largest oaks in North America. Gary A. Monroe @ PLANTS


Although once widespread in much of the northern Great Central Valley of California, California white oak now occurs primarily in the inner Coast Ranges and bordering foothills, For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site, Use soil moisture sensors to measure the soil moisture of Quercus lobata Née var. insperata Jeps..,


Adaptation: It grows in deep, fertile soils of flats and bottomlands below 1200 m. The climate is typically dry and hot, especially during the summer, with an average rainfall of 15 to 40 inches. Like most oaks, California white oak has an obligate relationship with mycorrhizal fungi, which provide critical moisture and nutrients. Some common associates in riparian habitats include coast live oak, sycamore, and cottonwoods, but sedges, grasses, and other herbaceous species are the dominant understory elsewhere. Propagation by Seed: Oak seeds do not store well and consequently seeds should be planted soon after maturity. Nuts are considered ripe when they separate freely from the acorn cap and fall from the tree. Care should be taken to collect local fruits, because they may be adapted to local environmental conditions. Viable nuts are green to brown and have unblemished walls. Nuts with discoloration or sticky exudates, and small holes caused by insect larvae, should be discarded. Direct Seeding: Unlike most other western oaks, white oak seeds germinate immediately following the first rains. Consequently, seeds should be planted soon after harvest to ensure establishment. Once a site is chosen, prepare holes that are 10 inches in diameter and 4 to 5 inches deep. One gram of a slow-release fertilizer should be placed in the bottom and covered by a small amount of soil. Place 6 to 10 acorns in each hole at a depth of 1 to 2 inches. Rodents or birds should use temporary enclosures to minimize herbivory. A simple enclosure can be constructed from a 1-quart plastic dairy container with the bottom removed and a metal screen attached. Near the end of the first season, seedlings should be thinned to 2 or 3 per hole and to 1 seedling by the second season. Supplemental watering may be necessary if a drought of 6 weeks or more occurs during the spring. Container Planting: Seeds may be planted in one-gallon containers, using well-drained potting soil that includes slow-release fertilizer. Tapered plastic planting tubes, with a volume of 10 cubic inches, also may be used. Seeds should be planted 1 to 2 inches deep and the soil kept moist. Seedlings should be transplanted as soon as the first true leaves mature. Planting holes should be at least twice as wide and deep as the container. Seedlings may require watering every 2 to 3 weeks during the first season. Care should be taken to weed and mulch around young plants until they are 6 to 10 inches tall.


General: Based on historic records, valley oak woodland has declined as a result of woodcutting, agriculture, and urban development, primarily in the Great Central Valley of California and in foothill bottomlands. Seedlings are especially sensitive to trampling and herbivory by cattle. Mature trees are susceptible to oak crown and root rot fungi (e.g., Inonotus, Ganoderma, and Laetiporus), that decay wood in trunks and roots. Consequently, activities that disturb or compact soil around trees, including construction and livestock grazing, need to be avoided or carefully managed within or near the zone of leaf canopy. Cultivars, Improved and Selected Materials (and area of origin) It is best to plant species from your local area, adapted to the specific site conditions where the plants are to be grown. Available from most native plant nurseries within its range. Contact your local Natural Resources Conservation Service (formerly Soil Conservation Service) office for more information. Look in the phone book under ”United States Government.” The Natural Resources Conservation Service will be listed under the subheading “Department of Agriculture.”

Plant Traits

Growth Requirements

Temperature, Minimum (°F)7
Adapted to Coarse Textured SoilsYes
Adapted to Fine Textured SoilsNo
Adapted to Medium Textured SoilsYes
Anaerobic ToleranceNone
CaCO3 ToleranceNone
Cold Stratification RequiredNo
Drought ToleranceMedium
Fertility RequirementMedium
Fire ToleranceLow
Frost Free Days, Minimum200
Hedge ToleranceNone
Moisture UseMedium
pH, Maximum7.5
pH, Minimum4.5
Planting Density per Acre, Maxim800
Planting Density per Acre, Minim300
Precipitation, Maximum40
Precipitation, Minimum16
Root Depth, Minimum (inches)42
Salinity ToleranceNone
Shade ToleranceIntolerant


Resprout AbilityYes
Shape and OrientationRounded
Active Growth PeriodSpring and Summer
C:N RatioHigh
Coppice PotentialNo
Fall ConspicuousYes
Fire ResistantNo
Flower ColorYellow
Flower ConspicuousNo
Foliage ColorGreen
Foliage Porosity SummerDense
Foliage Porosity WinterPorous
Foliage TextureMedium
Fruit/Seed ConspicuousYes
Nitrogen FixationNone
Low Growing GrassNo
Leaf RetentionNo
Known AllelopathNo
Height, Mature (feet)100.0
Height at 20 Years, Maximum (fee35
Growth RateRapid
Growth FormSingle Crown
Fruit/Seed ColorBrown


Vegetative Spread RateNone
Small GrainNo
Seedling VigorMedium
Seed Spread RateSlow
Fruit/Seed Period EndFall
Seed per Pound69
Propagated by TubersNo
Propagated by SprigsNo
Propagated by SodNo
Propagated by SeedYes
Propagated by CormNo
Propagated by ContainerYes
Propagated by BulbNo
Propagated by Bare RootYes
Fruit/Seed PersistenceNo
Fruit/Seed Period BeginSummer
Fruit/Seed AbundanceMedium
Commercial AvailabilityContracting Only
Bloom PeriodEarly Spring
Propagated by CuttingsNo


Veneer ProductNo
Pulpwood ProductNo
Protein PotentialLow
Post ProductNo
Palatable HumanNo
Palatable Browse AnimalLow
Nursery Stock ProductYes
Naval Store ProductNo
Lumber ProductNo
Fuelwood ProductHigh
Fodder ProductNo
Christmas Tree ProductNo
Berry/Nut/Seed ProductNo

<i>Quercus lobata</i> Née var. insperata Jeps.

<i>Quercus lobata</i> Née var. insperata Jeps.

<i>Quercus lobata</i> Née var. insperata Jeps.

<i>Quercus lobata</i> Née var. insperata Jeps.

<i>Quercus lobata</i> Née var. insperata Jeps.

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